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ORIGINAL RESEARCH ARTICLE
published: 03 December 2013
doi: 10.3389/fpsyg.2013.00912
Alterations in the sense of time, space, and body in the
mindfulness-trained brain: a
neurophenomenologically-guided MEG study
Aviva Berkovich-Ohana1*, Yair Dor-Ziderman2, Joseph Glicksohn2,3 and Abraham Goldstein 2,4
1Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
2The Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
3Department of Criminology, Bar-Ilan University, Ramat Gan, Israel
4Department of Psychology, Bar-Ilan University, Ramat Gan, Israel
Edited by:
Zoran Josipovic, New York
University, USA
Reviewed by:
Zoran Josipovic, New York
University, USA
Harry T. Hunt, Brock University,
Canada
*Correspondence:
Aviva Berkovich-Ohana, Department
of Neurobiology, Weizmann Institute
of Science, 234 Herzl St.,
Rehovot 76100, Israel
e-mail: aviva.berkovich-ohana@
weizmann.ac.il
Meditation practice can lead to what have been referred to as “altered states of
consciousness.” One of the phenomenological characteristics of these states is a
joint alteration in the sense of time, space, and body. Here, we set out to study
the unique experiences of alteration in the sense of time and space by collaborating
with a select group of 12 long-term mindfulness meditation (MM) practitioners in a
neurophenomenological setup, utilizing first-person data to guide the neural analyses. We
hypothesized that the underlying neural activity accompanying alterations in the sense
of time and space would be related to alterations in bodily processing. The participants
were asked to volitionally bring about distinct states of “Timelessness” (outside time) and
“Spacelessness” (outside space) while their brain activity was recorded by MEG. In order
to rule out the involvement of attention, memory, or imagination, we used control states of
“Then” (past) and “There” (another place). MEG sensors evidencing alterations in power
values were identified, and the brain regions underlying these changes were estimated
via spatial filtering (beamforming). Particularly, we searched for similar neural activity
hypothesized to underlie both the state of “Timelessness” and “Spacelessness.” The
results were mostly confined to the theta band, and showed that: (1) the “Then”/“There”
overlap yielded activity in regions related to autobiographic memory and imagery (right
posterior parietal lobule (PPL), right precentral/middle frontal gyrus (MFG), bilateral
precuneus); (2) “Timelessness”/“Spacelessness” conditions overlapped in a different
network, related to alterations in the sense of the body (posterior cingulate, right
temporoparietal junction (TPJ), cerebellum); and (3) phenomenologically-guided neural
analyses enabled us to dissociate different levels of alterations in the sense of the body.
This study illustrates the utility of employing experienced contemplative practitioners
within a neurophenomenological setup for scientifically characterizing a self-induced
altered sense of time, space and body, as well as the importance of theta activity in relation
with these altered states.
Keywords: space perception, time perception, body perception, magnetoencephalography (MEG), theta rhythm,
neurophenomenolgy, mindfulness meditation
INTRODUCTION
Long-term contemplative practitioners offer an exclusive oppor-
tunity to study unique mental states, due both to their heightened
introspective abilities, as well as their ability to intentionally
alter subtle aspects of consciousness (Lutz et al., 2007). Here, we
employ long-term Mindfulness meditators to study unique states
of alteration in the sense of time and space, which have not yet
been neuroscientifically investigated.
One of the characteristics of altered states of consciousness is
ajoint alteration in the experience of time and space (Tart, 1972;
Glicksohn, 1993; Baruss, 2003; Glicksohn and Berkovich-Ohana,
2011), which has been called by Fingelkurts and Fingelkurts
(2006) “a sense of timelessness, spacelessness.” The incidence
of mutual alteration in the experience of time and space is so
common that it led Walter Stace, the well-known scholar of
mysticism, to include one characteristic named “non-spatial and
non-temporal” (1960, p. 110) in his definition of the universal
core of mystical experience. According to Suzuki, sunyata,the
Buddhist concept of emptiness, means: “absolute emptiness tran-
scending all forms of mutual relationship...There is no time,
no space, no becoming, nothingness...when the mind is devoid
of all its possible content” (in Stace, 1960, p. 109). Similarly,
in Vedic psychology, transcendental consciousness, which is a
state achieved through the practice of Transcendental Meditation
in which the individual’s mind transcends all mental activ-
ity to experience the simplest form of awareness, is character-
ized by being unbounded in space and time (Alexander et al.,
1987).
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Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
Cognitively, an altered sense of time can be viewed as the
limit for the functioning of the cognitive timer, the breakdown
of apparent duration (Glicksohn, 2001). Apparent duration, in
turn,iscloselyrelatedtospatialperception(Boroditsky and
Ramscar, 2002; Glicksohn and Myslobodsky, 2006; Srinivasan
and Carey, 2010;reviewedbyWalsh, 2003). Neuroscientific
evidence suggests common underlying mechanisms for spatio-
temporal processing (Basso et al., 1996; Walsh, 2003; Danckert
et al., 2007; Oliveri et al., 2009a), as do linguistic (Boroditsky
and Ramscar, 2002; Núñez and Sweetser, 2006; Casasanto, 2008,
2010) and psychophysical studies (e.g., Sarrazin et al., 2004;
Oliveri et al., 2009a,b; Srinivasan and Carey, 2010). An altered
experience of space has been called by Stanley (1898) “space anni-
hilation,” again in relation to the time dimension. An altered
sense of time and space has hardly been studied scientifically,
the major obstacle being the production of these experiences
in the lab (but see the hypnosis experiment of Aaronson,
1970).
Phenomenologically, altered states of consciousness are fre-
quently accompanied by a joint alteration in both the experience
of time and space, as noted above, but also in bodily perception
(Tart, 1972; Travis and Pearson, 2000; Shanon, 2003; Vaitl et al.,
2005; Hunt, 2007; Ataria and Neria, 2013). Hence, we hypothe-
sizedthatanalteredsenseoftimeandspacewouldberelatedtoan
altered sense of body. An altered sense of body is conceptualized
as a disrupted sense of spatial unity between self and body, where
the self is not experienced as being confined within the bound-
aries of the body. A possible candidate mediating this connection
is the insula, related to both proprioception and the sense of time
(Craig, 2002, 2009a,b).
Mindfulness meditation (MM) practice focuses on cultivating
a non-judgmental awareness of momentary experience (Kabat-
Zinn, 2003) with the aim of liberation from human suffering
(Olendzki, 2003; Dreyfus and Thompson, 2007). While not being
the goal of training, long-term practice is often accompanied
by altered states of consciousness (Stace, 1960; Goleman, 1988;
Shapiro, 2008). This makes MM practitioners potentially famil-
iar with alteration in the experience of both time and space.
In addition, advanced practitioners have been documented as
not only being able to produce voluntary alterations of sub-
tle consciousness-related experiences within laboratory settings,
but also to provide refined first-person descriptions of these
experiences (Lutz et al., 2007). This renders MM practitioners
ideal candidates for the study of such unique states, which have
hitherto been quite unexplored.
Here,westudytheexperienceofalterationinthesenseof
time and space by collaborating with a select group of 12 long-
term MM practitioners in a neurophenomenological setup. All
of the participants have experienced these states in the past (see
Methods), and thus possess a frame of experiential reference. The
participants were asked to volitionally produce two distinct states,
which we apriorinamed “Timelessness” and “Spacelessness”
(outside time and space, respectively). In order to rule out the
involvement of attention, autobiographic memory or imagina-
tive processes (Szpunar et al., 2007), participants were also asked
to produce control states of “Then” and “There” (be in the
past and in another place, respectively). The data were ana-
lyzed in terms of “Timelessness” vs. “Now” and “Spacelessness”
vs.“Here,”andcontrastedwith“Then”vs.“Now”and“There”
vs. “Here” (two target and two control contrasts, respectively).
In particular, we investigated whether there would be similar
neural activity underlying both these states of “Timelessness” and
“Spacelessness.” Specifically, we hypothesized that: (1) the control
conditions, “Then” and “There,” would yield overlapping activ-
ity in an autobiographic memory network; (2) “Timelessness”
and “Spacelessness” conditions would overlap in a different net-
work, related to alterations in the sense of body, including the
insular cortex; and (3) phenomenologically-guided neural anal-
yses would yield further insight into the underlying physiology of
thealterationinthesenseoftimeandspace.
METHODS
PARTICIPANTS
Sixteen practitioners participated in this study, of whom two were
excluded due to self-reported severe tiredness and back pain,
respectively, during the data recordings. Two others were excluded
as they practiced different forms of meditation (not MM), in an
attempt to homogenize the group. The remaining participants
practice within the Theravada tradition. Participants were right-
handed (3 females, age 44.9 ±10.9 years, range: 31–64) and
healthy, with no history of mental or neurological diseases. All
participants were long-term practitioners with an average of 16.5
(SD =7.9, range: 9–34) years, and 11,225 (SD =9909, range:
1290–29,290) total hours, of meditation practice. The study was
approved by the Research Ethics Board of Bar-Ilan University.
The participants gave their written consent and were financially
compensated.
PRE-RECORDING PROCEDURES
The participants were introduced to the lab, then filled out forms
(research consent, personal details, formal practice estimate) and
Hood’s (1975) Mysticism scale, to test for previous experiences
of alteration in the sense of time and space. The experimenters
explained to the participants each part of the experiment, and
it was made certain that the participants understood the tasks.
Altogether, this part took 45–60 min.
Hood’s (1975) MYSTICISM SCALE (MSCALE)
Hood’s (1975) Mscale is a general measure of self-transcendent
experience, based on Stace’s (1960) conceptualization of eight
dimensions of transcendence. This is a 32-item scale, where the
items are grouped into eight components of experience: Positive
affect, Religious quality, Noetic quality, Ineffability, Unifying qual-
ity, Inner subjective quality, Ego quality,andTemporal and spatial
quality, the last being an experience of “timelessness” and “space-
lessness.” The results of the last item were used to assess whether
participants had previous experiences of altered sense of time and
space, of interest for this report. The four statements pertaining to
this item were: (1) I have had an experience which was both time-
lessness and spacelessness; (2) I have had an experience in which
I had no sense of time or space; (3) I have never had an expe-
rience in which time, place, and distance were meaningless; and
(4) I have never had an experience in which time and space were
non-existent. Participants were requested to indicate on a five-
point scale from −2(definitely not true)to+2(definitely true),
the extent to which each of 32 statements is true of their own
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Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
experiences. After reversing appropriate items, these responses are
converted to a five-point Likert scale, from 1 (low)to5(high),
where indecision is scored as 3.
The mean score for the Mscale was 4.30 ±0.40, indicat-
ing that participants experienced mystical states high above the
indecision point. Importantly, mean score for the sub-scale of
Temporal and spatial quality was high, 4.47 ±0.67. Thus, par-
ticipants had previous acquaintance with the concurrent expe-
rience of alteration in the sense of time and space. For com-
parison, the mean Mscale score in a population of 191 reli-
gious participants was 3.58, and the Temporal and spatial quality
was3.42(Lazar and Kravetz, 2005). This indicates that med-
itation practice increases the occurrence of alteration in the
sense of time and space experiences high above mere religious
tendency.
EXPERIMENTAL TASKS
The experiment comprised seven MEG recording sessions. Each
session was followed by an interview conducted via the intercom
system, during which brain activity was not recorded. The partic-
ipants were encouraged to stretch their limbs and relax during the
interviews, but were requested not to move and to keep their eyes
closed while performing the tasks. To correct for head and body
movements during the interviews, head-shapes were re-registered
at the beginning of each session. A 20-min break was suggested to
the participants after completing the 5th session of the experi-
ment, during which refreshments were offered. Total time in the
MEG was around 2 h.
The two sessions reported here are the “Time” and “Space” ses-
sions (3rd and 4th, respectively), which were preceded by a resting
state and a time production session, and followed by a “Self”
session, reported elsewhere (Dor-Ziderman et al., 2013). The par-
ticipants were asked to volitionally bring about alterations in their
experienceoftimeandspace,inamannerwhichhadbeenprevi-
ously explained. Each of the two sessions comprised 3 conditions,
each repeated 3 times in succession for 30s (Figure 1). A record-
ing with instructions for each condition was sounded (<2s),after
which the participant performed the requested task for 30 s. At
the end of the 30 s, a short sound was heard indicating the par-
ticipant to stop, and then the next instruction was delivered. The
session was followed by a structured interview conducted via the
intercom system.
The specific instructions for the three conditions in the “Time”
session were:
“Now”—“Try to be in the present moment”
“Then”—“Try to be in the near past (in the same place—the
lab)”
“Timelessness”—“Try to be outside time”
The specific instructions for the three conditions in the “Space”
session were:
“Here”—“Try to be here”
“There”—“Try to be elsewhere (at the moment, with the
experimenters outside the shielded MEG room)”
“Spacelessness”—“Try not to be in the center of space”
FIGURE 1 | Experimental protocol. The time and sequence of conditions
in the two MEG sessions of “time” and “space.” Yellow—“There”/“Then,”
blue—“Here”/“Now,” and purple—“Timelessness”/“Spacelessness”
conditions. All epochs were initiated by an auditory cue (marked by arrows).
SUBJECTIVE REPORTS
Phenomenological analyses
Participants were asked, immediately after each session, to
describe their experiences during the session, following a semi-
structured interview. The reports of the “Timelessness” and
“Spacelessness” conditions were carefully analyzed by the first
author.Twobroadthemesemerged:“senseoftimeandspace,”
and “bodily boundaries,” each including several categories of
experience. Subsequently, participants were allocated into one of
three categories for the “sense of time and space” theme, and into
one of four categories for the “bodily boundaries” theme. The
reports were then given to four other judges for anonymous rat-
ing. A classification of any report to one of the categories was
accepted based on the majority (minimum three out of five)
(Tab l e 1 ).
For the “sense of time and space” theme, three categories
emerged, all along a continuum of increasing alteration in the
sense of time and space:
(i) Regular sense of time and space (regular TS)—regular expe-
rience of time and space.
(ii) Change in the sense of either time or space (Change either
TS)—an alteration in the usual sense of time or of space.
(iii) Change in the sense of both time and space (Change both
TS)—an alteration in the usual sense of both time and space.
For the “bodily boundaries” theme, four categories emerged, the
first three along a continuum of alteration in bodily boundaries
and egocentric frame of reference:
(i) Regular bodily boundaries (regular BB)—regular experience
of bodily boundaries, fully egocentric experience.
(ii) Lower bodily boundaries (lower BB)—weaker than usual
experience of bodily boundaries, bodily expansion, a reduc-
tion in the egocentric experience.
(iii) Substantial loss of bodily boundaries (Substantial loss BB)—
very weak, and occasionally a total loss of experience of
bodily boundaries, strong bodily expansiveness, a strong
reduction in the egocentric frame of reference.
(iv) Out-of-body experience (OBE)—an extracorporeal egocen-
tric perspective (floating outside one’s body and perceiving
one’s physical body from a place outside one’s body), with
normal or distorted bodily boundaries.
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Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
Table 1 | Classification of participants to phenomenological categories and groups.
ID no. Timelessness description Category Spacelessness description Category Group
Body
boundary
Sense of
time/space
Body
boundary
Sense of
time/space
11 The fact that I tried to reach this state
obstructed it. The moment there was
intention there was a narrowing of the
space. But there were moments where I
felt outside time and space. There was a
vanishing of bodily sensations, although
there was awareness to awareness
itself. The purest form of the sensation
was there, but un-restricted. There was
relaxation and widening. The body was
not present. There were no body
sensations in the Timelessness
moments. In the pure awareness
moments there was no awareness to
bodily boundaries. There was spatial
expansion.
Substantial loss BB
Change both TS
The bodily dimension expanded but
there was no sense of boundless space,
rather that body dimensions have
changed. The body was wider and
wider. The body as physical image was
absent. There was a sense of open
space without the bodily dimension. The
mechanism that senses time was
absent. There was a sense of
immediateness, without a center aware
of temporality.
Substantial loss BB
Change both TS
BTS
12 It was a sense of un-knowing. It was
actually close to the present moment. I
had to let go of the present moment,
and it was subtle. Entering this
experience was through the present
moment, and then I had to leave the
world of experience in order to let go of
the present moment. I focused in not
knowing the moment. Like letting-go,
falling. The bodily sensation disturbed
and I had to let go of it again and again,
as it returned automatically.
Lower BB
Change both TS
It was a sense of spaciousness,
boundlessness, the center was not so
interesting, there was no clarity where
the center is and where is the periphery.
There was no quality of border.
Sensations were minimal compared to
the “Here” condition; the sense of
space occupied 90% of awareness.
Maybe there was a slight increase in a
visual sense of blackness, maybe
because associating space. I was not
aware of my self - boundaries. There
was a sense of timelessness in the
background.
Substantial loss BB
Change both TS
BTS
5 There was relaxation and letting-go,
emptiness, experience of bliss. Quiet,
wide, something wider than the body.
Like a long line crossed me and
continued beyond me. More open,
something relaxed in the muscles. A
wide experience with un-defined
boundaries. A sense of dissolving, that I
am dissolving, my body dissolving.
Substan ial loss BB
Change either TS
The metaphor is an amoeba, everything
spreads. A sense of nothingness,
emptiness. A sense of expansion.
There’s quiet, the hearing sharpens. A
part of the time I was outside myself, in
another world. There was no time.
Substantial loss BB
Change both TS
BTS
13 It was hard not to think of time, to be
outside time. After awhile Istarted
worrying about the time. It was most
similar to being in the present moment,
not being occupied with time. There was
no alteration in sensation, it was more
mental, but everything felt wider, and
there was no awareness to bodily and
self boundaries.
Substantial loss BB
Change either TS
When Iwas outside the center of space
the mind became more spacious and
exploring. There was no self-reference.
A state of wide and spacious mind.
There was less emphasis on the body,
more on the mental space. Time
seemed less important, not well
defined.
Lower BB
Change both TS
BTS
(Continued)
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Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
Table 1 | Continued
ID no. Timelessness description Category Spacelessness description Category Group
Body
boundary
Sense of
time/space
Body
boundary
Sense of
time/space
14 There was an expansion of the chest. I
lost discrimination between different
body parts. It felt pleasant, like a huge
hammock. A sense of expansion. There
was a spatial change, Iwas aware both
of the bodily boundaries as well as a
pleasant dissolution, something
liquid-like.
Substantial loss BB
Change either TS
It was like being in the tub hole where all the
water drains. Self-forgetfulness. A sense that
everything drains to me. Like wood barks, the
space outside, and suddenly a collapse into
my body. Like nylon that you stretch and let go
of repeatedly. . . Bodily sensations were wider.
Bodily space was larger. Much less awareness
to my self boundaries. There was no change in
the sense of time.
Lower BB
Change either TS
BTS
4 The mind was in the present moment,
as this is the gate to timelessness. I felt
pressure to succeed, and that time was
too short to enter a “blackout,” which is
for me a Timelessness dimension. There
was awareness to body and breath, I
was aware of the subject-object duality.
Regular BB
Regular TS
I released the subject-object contrast, and
then the center of space became endless,
without areference point in the middle. There
was a sense of floating in a sea of being.
Experiences arise, but no emotions, no
sounds. Everything was a part of one
conscious experience. The dichotomy
between subject and object dissolved. There
was no reflective awareness of “this is a
sound.” Everything was a part of a singular
event. The experience of the body faded.
There was a sense of body in the background,
not in front of consciousness. There were no
self boundaries, only fusion with everything
that exists. There was achange in the sense
of time, time lost its linearity.
Substantial loss BB
Change both TS
NTS
9 All the time I focused on visualizing
black, as if I see darkness, not
considering anything related with time.
There was no sensory alteration, but I
was less aware of how much time
passed. There was awareness to space,
but lower than usual. Fifty percent of the
time Iwas not aware of my bodily
boundaries.
Substantial loss BB
Change both TS
I was imagining that the body is un-real,
fragmented all over the place, breaking apart. I
used perception—the mind is not mine, it’s
only processes in time. It’s not I who is
thinking, thoughts exist, simply energy. It’s not
me who is in the space. There was no
alteration in bodily sensations. I was not aware
of the mental side, and less aware of the
physical side. There was an alteration in the
sense of time. When Irelated to the body as
non-existent it became abstract and time was
less relevant.
Regular BB
Change either TS
NTS
1 I wasn’t outside time. I tried not to
localize myself, not knowing where I am
in time, not to control my thoughts, not
even to here. There was an alteration in
bodily sensation in the direction of less, I
cannot define it.
Lower BB
Regular TS
I let myself be very big, expand. There was
little awareness to different body parts, more
something like not exactly I. Mainly a sense of
expansion, something open and wide. Little
bodily boundaries compared to the usual
feeling. Little instances of awareness to my
boundaries. There was no change in the sense
of time.
Lower BB
Change either TS
NTS
(Continued)
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Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
Table 1 | Continued
ID no. Timelessness description Category Spacelessness description Category Group
Body
boundary
Sense of
time/space
Body
boundary
Sense of
time/space
6 The mind could not produce this
condition. There was a sense of the
body, many bodily sensations.
Regular BB
Regular TS
It was hard to differentiate space from time. It
was a little more successful than the
Timelessness condition, but didn’t put me
outside space. I let myself rest within the
sensations, than the sense of time and space
becomes vague, there was just presence.
Regular BB
Change either TS
TS
2 It started with momentary experience,
as I usually enter timelessness through
momentary experience. Itried to dim
concrete signs of momentary
experience, like body and breath. I tried
to be less focused on what is happening
now, like sensory experience.
Regular BB
Regular TS
It was like before with Timelessness. I started
with momentary sensation of my body lying
down, and then Itried to expand the
experience. Meaning, to dim bodily boundaries
and to see if I can experience myself wider,
extended, less physically bounded. The focus
was trying to dim bodily boundaries; Igave
less attention to what is happening in the time
domain.
Lower BB
Regular TS
NTS
16 It was like floating, trying to remain in a
letting go state. The bodily boundaries
did not change, there was no sensory
change, it was more mental.
Regular BB
Regular TS
I tried to be in a state of rest where it’s as if I
lose my center, my thought, and it alternated.
Apleasant bodily sensation. A regular sense of
self. Much less sense of time.
Regular BB
Change either TS
NTS
8 It was very hard to maintain, every
sound disturbed it, it was about being
very quiet and concentrated, a very
visual experience. It jumped to my mind
“I’m floating outside the earth and
atmosphere.” Isaw the time-line from a
bird view. There was no awareness of
momentary physical sensations, only
awareness to bodily boundaries. I took
myself to a different space, I wasn’t
here. But Iwas with my body, just
floating in outer space. The body was
identical, Iwasn’t floating as
consciousness, but as abody.
OBE
Change both TS
The body stayed in bed but I saw myself from
the corner of the room. The first time (first
30 s) it was continuous. The second time it
was hard to maintain and Ikept entering and
leaving my body. In the third time I came back
to the corner and it was more successful.
Outside the body I felt short and small, like a
little child, I shrank. Iwent in and out of bodily
borders. It’s hard to say if there was any
temporal change. The third time seemed too
short.
OBE
Change both TS
Excluded
Yellow and cyan, sentences pertaining to body or to time/space, respectively. BB, bodily boundaries; OBE, Out of body experience; TS, time and space; BTS, Both
time and space; NTS, Not both Time and Space.
In line with this analysis, 11 participants could be placed along
a continuum of alteration in bodily boundaries and egocentric
frame of reference. As the OBE could not be placed along the
continuum of reduction in egocentric frame of reference, the sole
participant having this experience was excluded from all subse-
quent analyses (see Tab l e 1 ). The remaining 11 participants were
included in the subsequent analyses, and were regarded as being
placed along one continuum: at one end were those who expe-
rienced a weak and gentle shift, while at the other end were
those who experienced a profound shift. This is in line with
Shapiro (2008) who states that unique meditative states “need
to be seen along a continuum. On one hand of the continuum
are “full blown” mystical experiences, at the other, more common
alterations of perception” (p. 25). Next, we set out to differentiate
between participants along the higher and lower ends of the above
continuum, by creating two groups (Tab l e 1):
(1) Both Time and Space (BTS) group—during the two con-
ditions of “Timelessness” and “Spacelessness,” participants
experienced a change in both themes of phenomenal
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Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
experience (i.e., do not belong to “Regular BB” or “Regular
TS”).
(2) Not both Time and Space (NTS) group—during the two con-
ditions of “Timelessness” and “Spacelessness,” participants
did not experience a change in both themes of phenomenal
experience (i.e., belong to “Regular BB” or “Regular TS”).
Testing for differences between the BTS and NTS groups, there
were no significant differences in age or practice experience, as
well as mean score for the Mscale or the sub-scale of Tem p o r a l
and spatial quality.
Success and stability ratings
Participants were asked to verbally rate, on a 1–10 scale (1—“very
low,” 10—“very high”), their success (defined here as: how strong
was the experience, on average, across the 90s allocated for each
condition) and stability (defined here as: how stable was the expe-
rience during the 90 s allocated for each condition) in performing
each of the tasks. Subsequently, a Three-Way ANOVA was con-
ducted, with Session (Time/Space) ×Condition (Then/There,
Here/Now, Timelessness/Spacelessness) ×Measure (success, sta-
bility) on these ratings. There was no difference between suc-
cess and stability (Figure 2A), hence we will focus subse-
quently on success. We found only a main effect for Condition
[F(2,20)=18.5, MSE =5.07, p<0.0001]. The “Timelessness”
and “Spacelessness” conditions were rated as significantly less suc-
cessful compared to “Here” and “Now” [t=3.80, p=0.011 and
t=3.99, p=0.0045, respectively, Bonferroni-corrected post-hoc
paired t-tests], but showed no significant difference between
them. When comparing scores for the “Timelessness” and
“Spacelessness” conditions between the BTS and NTS groups,
no significant difference was found. Figure 2B depicts the rating
for the “Timelessness” vs. “Spacelessness” conditions, showing
the BTS and NTS groups to be similarly distributed. This is in
contrast to the phenomenological difference found between the
groups. We suggest that the discrepancy stems from different lev-
els of self-criticism, as well as different personal expectations.
In fact, some of the most-experienced practitioners scored their
success as being lower compared to the less-experienced prac-
titioners. Altogether, our results emphasize the need to collect
verbal reports in addition to self ratings when conducting neu-
rophenomenological analyses.
FIGURE 2 | Rating of task success and stability. (A) Participants’ rating
(Mean ±s.e.m., n=12) for success and stability during the different
conditions. ∗p<0.05, ∗∗p<0.005, Bonferonni-corrected; (B) A scatterplot
for the Timelessness vs. Spacelessness rated success. BTS, Both time and
space; NTS, Not both Time and Space. Yellow dot refers to one OBE
participant.
An additional observation is that the “Timelessness” scores
were more variable compared to the “Spacelessness” scores. The
reason for this is that two of the three participants report-
ing zero success in the “Timelessness” condition belong to the
Burmese Mahasi school, which adheres strictly to the “Progress
of insight” which is an inner “map” of how insights unfold
through 16 developmental stages of insight knowledge. This
tradition encourages an experience of “cuts” in consciousness,
which are considered the culmination of these stages, and are
called fruition (phala). Nanarama (1983) describesthisstate:
“consciousness...transcends the continuous occurrence of for-
mations and aligns upon non-occurrence” (p. 117). The fruition
is mentioned here in some length, as it turned out that these
two participants attempted to reach this acquainted state unsuc-
cessfully during the short time allocated to the “Timelessness”
condition, which affected their rating of success. However, after
the Time session, it was emphasized that the experimenters did
not expect these unique fruition states during the short lab proce-
dure, thus their scores for the “Spacelessness” condition increased
markedly,to6and8.
MAGNETOENCEPHALOGRAPHY (MEG)
MEG data acquisition
MEG recordings were conducted with a whole-head, 248-channel
magnetometer array (4-D Neuroimaging, Magnes 3600 WH) in
a magnetically-shielded room. Reference coils located ∼30 cm
above the head oriented by the x,y,andzaxes were used to
remove environmental noise. Head position was indicated by
attaching 5 coils to the scalp and determining, to a 1 mm res-
olution, their position relative to the sensor array before and
after measurement. Head localization was performed before and
after each set of tasks to determine degree of head movement.
Head shape and coil position were digitized using a Pollhemus
FASTTRAK digitizer. Brain signals were recorded with a sampling
rate of 1017.25 Hz and an analog online 0.1–400 Hz band-pass
filter. The instructions for each condition were presented using
E-prime 1.0 and delivered via a STAX SRS-005 amplifier and
SR-003 push-pull electrostatic ear speakers coupled by a vinyl
tube to silicon earpieces to prevent magnetic noise within the
shielded room. Task performance ratings were collected using a
LUMItouch photon control response box.
MEG data cleaning and preprocessing
Data processing and analysis was performed using Matlab®
R2009b and FieldTrip toolbox for MEG analysis (Open source
software for advanced analysis of MEG) (Oostenveld et al., 2011).
Data were cleaned for line frequency (by recording on an addi-
tional channel the 50 Hz from the power outlet, and subtracting
the average power-line response from every MEG sensor), and
24 Hz building vibration (measured in x,y,andzdirections
using 3 Bruel and Kjaer accelerometers) artifacts (Tal and Abeles,
2013). The data from the 3 “Time” and 3 “Space” conditions were
then segmented into non-overlapping 2-s epochs. Each epoch was
visually examined for muscle and jump artifacts (in the MEG
sensors). Contaminated epochs were discarded. No malfunction-
ing MEG sensors were identified. To ensure the removal of all
heartbeat, eye and muscle artifact, an independent component
analysis (ICA) was performed on the data (Jung et al., 2000).
www.frontiersin.org December 2013 | Volume 4 | Article 912 |7
Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
Segmented data were down-sampled to 339 (1017/3) Hz to speed
up data decomposition. The data were then decomposed into a
set of independent components (248, equal to the number of sen-
sors) ordered by degree of their explained variance. Components
indicating heartbeats or eye movements were determined from
a visual inspection of the 2D scalp maps and time course of
each component. The remaining components were then used to
reconstruct the pre down-sampled data.
Sensor-level analyses
The first 4 s of each task (3 tasks of 30-s in each condition) were
omitted so as to allow the participants sufficient time to enter the
states. This decision was made after consulting an expert medita-
tor as to the study design, and following two self-pilot runs (with
Aviva Berkovich-Ohana and Yair Dor-Ziderman, also long-term
practitioners). From the remaining data in each condition, the
first 32 epochs were used for further sensor-level analyses. These
2-s epochs were multiplied by a Hanning taper, and subjected to
a Fast Fourier Transformation (FFT) for the frequencies ranging
from 4 to 45 Hz. This resulted in a power spectrum with a fre-
quencyresolutionof0.5Hzforeachepoch.Thepowerspectra
were then averaged across the epochs of each condition and across
the theta (4–8 Hz), alpha (8–13 Hz), beta (13–25 Hz), and gamma
(25–45 Hz) frequency bands, thus obtaining mean power for each
condition, participant and frequency band.
Sensor-level cluster-based statistics were assessed, and cor-
rected for multiple comparisons, using a Monte-Carlo non-
parametric permutations approach (Maris and Oostenveld,
2007). This approach was chosen as it does not make any assump-
tions on the underlying distribution. Finally, 2D t-value scalp
topographies marking the significant clusters were created.
Source-space projection
Localization was performed for all frequency bands. Sources
were estimated using Synthetic Aperture Magnetometry (SAM,
Robinson and Vrba, 1999). SAM is an adaptive non-linear
minimum-variance beamformer algorithm. It calculates the sig-
nal covariance from the MEG sensor data and uses it in con-
junction with a forward solution for the dipoles at each 3D brain
voxel (of a specified size) to construct optimum spatial filters. The
spatial filtering suppresses interference of unwanted signals from
other locations.
For source estimation, the pre-ICA data were used. Data were
band filtered (using the SAM default IIR filter) for each partic-
ipant and condition and frequency band. Covariance matrices,
and subsequently SAM weights, were computed for each 5mm
cubic voxel using the data from the two conditions participat-
ing in each signal change calculation, for each frequency-band-
filtered time-series data. For each voxel, the data were multiplied
by the weights, thus creating “virtual sensor” time-series, which
were then transformed via FFT to the frequency domain, thus
deriving power values. The next step involved calculating, for each
frequency of each sensor of each participant, a power signal (SC)
metric, for estimating activity differences between contrasted
conditions. For normalization, SC was computed using a log
ratio. More specifically, for sensor S,frequencyf, and power values
of conditions Aand B,SC[S(f)]=log(A/B). Each participant’s
SC values for each of the comparisons were then collapsed across
all sensors, and averaged across the frequency bands specified
above in the sensor-level analysis.
To facilitate group analysis, head models were constructed
by co-registering each participant’s SAM volume to a previously
obtained MRI scan (T1-weighted anatomical images acquired
with high-resolution 1-mm slice thickness, obtained by Aviva
Berkovich-Ohana, by means of a 3T Trio Magnetom Siemens
scanner located at the Weizmann Institute of Science, Rehovot,
Israel), based on the position of the fiduciary markers established
during the digitization phase. Each participant’s MRI and its
co-registered SAM volume were then transposed into a common
Talairach anatomical space (Talairach and Tournoux, 1988).
Voxel-level group statistics, for each comparison and frequency
band, were conducted using one-sample t-tests against the
null hypothesis that the SC measures came from a continuous,
normal distribution with a zero mean, and corrected for multiple
comparisons based on a Monte Carlo simulation of random
noise distribution (using AFNI’s 3dClustSim module) (Forman
et al., 1995).
RESULTS
We first tested for significant differences in power between the
“Here” and “Now” conditions, which were considered to be the
baseline states for the other conditions. Importantly, there were
no significant differences between them in any of the four fre-
quency bands tested. Testing the “Spacelessness” vs. “Here” and
the “Timelessness” vs. “Now” contrasts, we found clusters of sig-
nificant differences only within the theta band (p=0.014, and
p=0.049, respectively). Figure 3 provides 2D topographic rep-
resentations of the sensor-level t-values for these two significant
contrasts. As could be expected, the two contrasts evidence a
different topography. The significant clusters for “Spacelessness”
vs. “Here” occur predominantly over bilateral central-frontal
electrodes, while “Timelessness” vs. “Now” shows central and
right lateralized theta activity. However, there is an overlap-
ping region (right central), which is further explored at the
source level.
To examine the neural activity underlying the conditions of
“Timelessnes” and “Spacelessness,” “Timelessness” was compared
FIGURE 3 | 2D scalp maps of theta power SC contrasts. 2D topographic
representations of significant sensor-level theta power (4–8 Hz) SC for the
Timelessness vs. Now (Right), and Spacelessness vs. Here (Left). Crosses
on the map represent significant clusters; color bar scale indicates t-values.
Frontiers in Psychology | Consciousness Research December 2013 | Volume 4 | Article 912 |8
MEG SENSOR-LEVEL RESULTS
MEG SOURCE LOCALIZATION ESTIMATES
Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
to “Now,” and “Spacelessness” was compared to “Here.” Although
the sensor-level analyses guided our source localization toward
the theta frequency, we validated these results by searching for
an overlap between the time and space comparisons over all fre-
quency bands. Overlapping clusters were found only within the
theta band, indicating increased activity. While not being the
main goal of this study, we nevertheless report the “Timelessness”
and “Spacelessness” activity patterns, before focusing on their
overlapping activity.
“Timelessness” vs. “Now” (Figure 4,Tab l e 2 ) showed mostly
right-lateralized (88%) theta activity spanning several regions,
including right motor areas [postcentral gyrus and middle frontal
gyrus (MFG)], parietal lobule, thalamus, basal ganglia, bilateral
cerebellum, right temporal gyrus, right insula, right somatosen-
sory and bilateral medial posterior cingulate cortices (PCC,
including precuneus and cuneus). Spacelessness vs. Here showed
theta activity which was bilaterally distributed (54% right hemi-
sphere), over several regions (Figure 4,Tab le 2 ). It included
bilateral PCC (with precuneus), bilateral cerebellum, bilateral
parahippocampus, right basal ganglia, bilateral temporal gyrus,
left thalamus, right postcentral gyrus, MFG right parietal lobule,
and a small portion of the right insula. The “Timelessness” and
“Spacelessness” conditions overlapped at the posterior part of the
right superior temporal gyrus (STG), left cerebellum, and bilat-
eral posterior cingulate cortex and adjacent precuneus (PCC/Prc)
(Figure 4,Tab l e 3 ).
FIGURE 4 | Beamforming source estimates for the overlap between
Timelessness vs. Now and Spacelessness vs. Here contrasts in the
theta (4–8 Hz) frequency. Axial, sagittal and coronal views (left to right) of
group (n=11) SAM pseudo-Fsource estimates overlayed on the Colin
template. Note that in all images right and left sides are crossed. Green,
orange, and red indicate Timelessness, Spacelessness and overlap
between conditions, respectively. Top : left cingulate/precuneus and culmen
(clusters 2 and 4, respectively, Table 3); Center: right cingulate/precuneus
(cluster 1, Table 3); Bottom: right superior temporal gyrus (cluster 3,
Table 3).
In order to control for attention, memory or imagination
processes, we contrasted, in source space, the “Then” vs. “Now”
and“There”vs.“Here’conditions,andthenlookedforanover-
lapbetweenthem.Asbefore,whilefocusingonthethetarhythm,
we checked for overlapping regions over all frequency bands.
Overlapping clusters were found mostly within the theta band,
with the only exception being one alpha band cluster local-
ized exactly (same 10 voxels) over theta cluster no. 1, on the
right superior parietal lobule (Figure 5,Ta bl e 3 ). The two con-
trasts overlapped in three clusters, which included four main
regions: Right posterior parietal lobule (PPL), right precen-
tral and MFG, and bilateral precuneus (Figure 5,Tab l e 3 ). Yet,
there were regions which did not overlap between the two con-
trasts (Ta b l e 4 ). These included the right superior temporal gyrus
(STG), which although activated in both contrasts, did not over-
lap. Additionally, only “Then” vs. “Now” activated the right
insula, and only “There” vs. “Here” activated the right anterior
cingulate and right lateral cerebellum.
To study possible differences between the BTS and NTS groups,
we derived for each participant the mean theta activity value
within each of the four clusters of overlap between the
“Timelessness” and “Spacelessness” conditions. On these val-
ues, we ran a Three-Way ANOVA with one grouping factor
(BTS, NTS) and repeated measures on Condition (Timelessness,
Spacelessness) ×Cluster (R-PCC, L-PCC, R-STG, cerebellum).
There was no main effect for Condition, Cluster or Group.
However, we found a significant Group ×Cluster interaction
[F(3,27)=2.85, MSE = 0.001, p<0.05]. As can be seen in
Figure 6, the BTS group exhibited lower R-STG and higher
L-cerebellum theta activity compared to the NTS group.
While the insula showed theta activity during both
“Timelessness” and “Spacelessness,” the activity pattern was
not overlapping. As a result, this region does not appear as an
overlapping cluster. However, in order to test the hypothesis
that group differences in bodily boundaries are related to insula
activity, as the insula is a major interoceptive regions (Craig,
2002), we defined the insula anatomically as an ROI, and then
calculated the theta activity value within the bilateral insula for
the overlap between the “Timelessness” and “Spacelessness”
conditions. On these values, we ran a Three-Way ANOVA on
Group (BTS, NTS) ×Condition (Timelessness, Spacelessness) ×
Hemisphere (L, R). Two outliers with very high values (above two
standard deviations from the group mean) for the “Spacelessness”
condition, one from each group, were excluded. We found a
Condition ×Hemisphere interaction [F(1,7)=5.52, MSE =
0.002, p<0.05], with “Spacelessness” being left-lateralized, and
“Timelessness” being right-lateralized (the latter being significant
[p <0.05, Bonferroni-corrected, post-hoc t-test]) (Figure 7A).
Importantly, we found a main effect for Group [F(1,7)=6.12,
MSE = 0.006, p<0.05], with the BTS group showing lower
overall insula theta activity compared to NTS (Figures 7B,C).
For comparison purposes, we show the mean theta activity
value within each of the four clusters of overlap between the
“Timelessness” and “Spacelessness” conditions for the one par-
ticipant who reported an OBE (Figure 8). In comparison with
www.frontiersin.org December 2013 | Volume 4 | Article 912 |9
NEUROPHENOMENOLOGICALLY-GUIDED MEG ANALYSIS
Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
Table 2 | Beamforming solutions for the contrasts Timelessness vs. Now and Spacelessness vs. Here in the theta (4–8Hz) frequency band
(n=11) .
Overlapped
conditions
Cluster
(no. voxels)
TLRC coordinates (mm, RAI) Hemisphere overlap Regions included in cluster (atlas TT_Daemon)
xYzL (%) R (%) Name Voxels
Timelessness vs. Now
1 (529) −47.537.547.5 18 72 Precuneus 104
Cingulate gyrus 63
R. Postcentral gyrus 60
R. Inferior parietal lobule 41
R. Precentral gyrus 40
Paracentral lobule 35
R. Middle frontal gyrus 19
Culmen 19
Cuneus 15
R. Superior parietal lobule 13
Uvula 12
2 (253) −67.522.5−7.5 0 97 R. Superior temporal gyrus 63
R. Insula 61
R. Middle temporal gyrus 38
R. Thalamus 23
R. Lentiform nucleus 12
R. Transverse temporal gyrus 8
R. Claustrum 6
3 (22) −17 .5−7.517.5 0 96.7 R. Caudate 9
R. Anterior cingulate 4
Spacelessness vs. Here
1 (204) 17.5−12.547.5 89 7 Superior frontal gyrus 45
Medial frontal gyrus 42
Cingulate gyrus 40
Middle frontal gyrus 24
Paracentral lobule 18
Precuneus 3
2 (149) −37.5−12.5−22.5 0 99 R. Inferior frontal gyrus 24
R. Superior temporal gyrus 23
R. Uncus 19
R. Lentiform nucleus 15
R. Parahippocampal gyrus 13
R. Subcollosal gyrus 4
R. Caudate 3
R. Insula 3
3 (73) −67.522.5−12.5 0 97 R. Inferior temporal gyrus 21
R. Fusiform gyrus 12
R. Culmen 9
R. Cerebellar tonsil 6
R. Middle temporal gyrus 3
(Continued)
Frontiers in Psychology | Consciousness Research December 2013 | Volume 4 | Article 912 |10
Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
Table 2 | Continued
Overlapped
conditions
Cluster
(no. voxels)
TLRC coordinates (mm, RAI) Hemisphere overlap Regions included in cluster (atlas TT_Daemon)
xYzL (%) R (%) Name Voxels
4 (72) −37.537.557.5 0 89 R. Postcentral gyrus 17
R. Inferior parietal lobule 14
R. Superior parietal lobule 11
R. Precuneus 10
5 (52) 2.542.5−2.5 94 0 L. Posterior cingulate 24
L. Culmen 13
L. Cerebellar lingual 3
6 (44) 52.547.5−2.5 100 0 L. Middle temporal gyrus 28
L. Inferior temporal gyrus 3
7 (33) 32.542.5−42.5 100 0 L. Cerebellar tonsil 5
8 (33) −42.5−12.547.5 0 78 R. Middle frontal gyrus 22
R. Superior frontal gyrus 8
9 (22) 2.512.517.5 98 2 L. Thalamus 10
L. Parahippocampal gyrus 3
10 (15) −67.57.52.5 0 88 R. Superior temporal gyrus 13
11 (13 ) −12.537.532.5 0 100 R. Cingulate gyrus 11
Information supplied includes number of voxels in each cluster, center of cluster characteristics, hemispheric overlap, brain regions, and number of voxels in the
region. Only clusters >2 voxels are presented. The Afni-supplied TT Daemon atlas was used. Due to poor resolution and signal leakage to non-brain regions, overlap
percen tages d o not always add up to 100%.
the BTS and NTS groups, the OBE participant exhibited much
lower bilateral PCC and left cerebellar values. Right MTG and
total insula values were slightly higher than the NTS group.
DISCUSSION
Significant differences in power between the “Spacelessness” vs.
“Here” as well as the “Timelessness” vs. “Now” contrasts were
found only within the theta frequency. Both contrasts showed
maximal theta power over the right hemisphere. This result is in
line with accumulating evidence from animal and human stud-
ies, showing that theta activity is tightly related to space and
time processing, i.e., encoding and retrieval (recently reviewed by
Hasselmo and Stern, 2013). This is also in agreement with the
notion that there is a right-hemisphere specialization for space
and time processing (Rao et al., 2001; Ellison et al., 2004; Oliveri
et al., 2009a,b;reviewedbyWalsh, 2003).
The production of theta with eyes closed is a well-known
accompaniment of states of deep relaxation such as stage 1 sleep,
meditation and hypnosis (Vaitl et al., 2005). Gruzelier (2009)
reviews EEG-neurofeedback (NF) training studies for increas-
ing theta activity, showing wide behavioral effects, including
increased creativity, heightening psychological integration, relief
from anxiety and depression and resolved post traumatic stress
syndrome. Phenomenologically, participants in this EEG-NF
protocol reported increased theta “to be associated with a deeply
internalized state and with a quieting of the body, emotions,
and thought” (Gruzelier, 2009, p. 102). Based on the findings
that theta oscillations play a critical role in the coupling and
integration of widely distributed neural circuits (Vo n S t ei n a n d
Sarnthein, 2000), as well as the EEG-NF results, Gruzelier (2009)
proposed that the wide ranging behavioral correlates of theta
result from theta’s role in mediating distributed circuitry in the
brain, relating the concepts of psychological integration (integra-
tive experiences leading to feelings of psychological well-being)
and neural integration.
The “Timelessness” and “Spacelessness” conditions represent
alterations in the sense of time and space, akin to those reported
in various meditative practices, and can be compared to previ-
ously reported theta topography in studies of meditative states.
The increased frontal-central theta power (Figure 3)isinaccord
with ample meditation studies, reporting increased theta activ-
ity, mostly over frontal-central sites (Hebert and Lehmann, 1977;
Aftanas and Golocheikine, 2001; Kubota et al., 2001; Faber et al.,
2004; Cahn and Polich, 2006; Slagter et al., 2009; Baijal and
Srinivasan, 2010). Increased theta in meditation studies has been
interpreted as reflecting internalized attention (Cahn and Polich,
2006), space and time processing (Baijal and Srinivasan, 2010),
as well as being related, especially when manifesting as theta
bursts, to deep meditative states, feelings of blissfulness and low
www.frontiersin.org December 2013 | Volume 4 | Article 912 |11
MEG SENSOR-LEVEL RESULTS
Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
Table 3 | Beamforming solutions for the overlapping contrasts between Timelessness/Spacelessness and Then/There in the theta (4–8Hz)
frequency band (n=11) .
Overlapped
conditions
Cluster
(no. voxels)
TLRC coordinates (mm, RAI) Hemisphere overlap Regions included in cluster (atlas TT_Daemon)
xYzL (%) R (%) Name Voxels
Timelessness vs. Now and
Spacelessness vs. Here
1(13) −10.2 41.7 31.3 0 100 R. Cingulate gyrus 11
R. Precuneus 1
R. Posterior cingulate 1
2(13) 7.1 31.3 42.1 100 0 L. Cingulate gyrus 7
L. Paracentral lobule 3
L. Precuneus 1
3(11) −54.316.1 3.0 0 100 R. Superior temporal gyrus 11
4(9) 5.851.9 0.3100 0 L.Culmen 6
l. Posterior cingulate 1
L. Lingual gyrus 1
Then vs. Now and
There vs. Here
1 (30) −33.3 57.3 47.2 0 94 R. Superior parietal lobule 10
R. Inferior parietal lobule 8
R. Precuneus 5
2(14) −43.97.5 49.6 0 86 R. Precentral gyrus 12
R. Middle frontal gyrus 2
3(7) 7.5 42.5 56.1 100 0 L. Paracentral lobule 4
L. Precuneus 2
Information supplied includes number of voxels in each overlapping cluster, center of cluster characteristics, hemispheric overlap, brain regions, and number of
voxels in the region. Only clusters >1 voxels are presented. The Afni-supplied TT Daemon atlas was used. Due to poor resolution and signal leakage to non-brain
region s, overlap p ercentages do not always ad d up to 100%.
thought content, and a sense of integration (Kasamatsu and Hirai,
1966; Hebert and Lehmann, 1977; Aftanas and Golocheikine,
2001).
The results are also in agreement with the junction-point-
model hypothesis proposed by Travis (1994).Briefly,Travis
proposes that bursts in the 7–9 Hz band underlie the state of
transcendental consciousness (Travis, 1994), which is “the least
excited state of mental activity,” unbounded by a sense of time
and space (Alexander et al., 1987). Travis suggests that tran-
scendental consciousness underlies other forms of consciousness,
and can be seen especially during transitions between different
states of consciousness. He then provides support for his hypoth-
esis by showing increased 7–9 Hz activity during the transi-
tion between waking, NREM-sleep, and REM-dreaming. Similar
theta activity has also been reported during Transcendental
Meditation (TM); and in TM practitioners, it also unusu-
ally accompanies sleep, a state called witnessing sleep (Travi s ,
1994). This state differs from lucid dreaming by increased
“separateness” and reduced dream control (Alexander, 1988).
The junction-point model ties all these states as windows to
an underlying field of transcendental consciousness, related to
alterationsinthesenseoftimeandspace,andasenseof
boundlessness.
Taken together, the literature on theta in neurofeedback and
meditation suggests that this is the optimal bandwidth for inte-
gration and synthesis across neural regions. As Hunt (2007,p.
226) argues, “widespread EEG theta would appear to be the level
of activation which affords a maximized coherence across the
widestpossible neural areas....” Thisinterpretation aptly fits the
phenomenology of the “Timelessness” and “Spacelessness” states,
which include many descriptions of integration (Tab l e 1 ): “The
purest form of the sensation was there, but un-restricted. There
was relaxation and widening” and “There was a sense of open
space without the bodily dimension” (participant no. 11); “It
was a sense of spaciousness, boundlessness...there was no clar-
ity where the center is and where is the periphery. There was no
quality of border” (participant no. 12); “There was relaxation and
letting-go, emptiness, experience of bliss, quiet, wide” and “The
metaphor is an amoeba, everything spreads. A sense of noth-
ingness, emptiness. A sense of expansion” (participant no. 5);
“I lost discrimination between different body parts. It felt pleas-
ant, like a huge hammock. A sense of expansion” (participant
no. 14); “The center of space became endless, without a refer-
ence point in the middle. There was a sense of floating in a sea of
being... Everything was a part of one conscious experience. The
dichotomy between subject and object dissolved...Everything
Frontiers in Psychology | Consciousness Research December 2013 | Volume 4 | Article 912 |12
Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
FIGURE 5 | Beamforming source estimates for the overlap between
Then vs. Now and There vs. Here contrasts in the theta (4–8Hz)
frequency. Axial, sagittal, and coronal views (left to right) of group (n=11)
SAM pseudo-Fsource estimates overlayed on the Colin template. Note
that in all images right and left sides are crossed. Green, orange and red
indicate Then, There and overlap between conditions, respectively. To p :left
paracentral lobule and precuneus (cluster 3, Table 3). In the sagittal view,
the same cluster (red) is compared with left cingulate/precuneus activity
(cyan) for the Timelesness/Spacelessness overlap (cluster 2, Table 3). Note
the clear separation between the superior cluster found in the Then/There
overlap, and the inferior cluster found for the Timelesness/Spacelessness
overlap; Center: right precentral and middle frontal gyrus (cluster 2,
Table 3); Bottom: posterior parietal lobule (cluster 1, Table 3).
was a part of a singular event. The experience of the body faded”
(participant no. 4). Indeed, Faber et al. (2012) discuss the ques-
tion, “Why are there so few systematic reports on subjective
experience during meditation,” and emphasize that “it could be
very useful in sorting out brain states of different cogitations” (p.
262). In this study, we have shown how such reports can be uti-
lizedinaproductiveway,bothtoaidininterpretingbrainactivity
during these unique states, but also to learn more about these
states, from the systematic self observations of our meditators.
One does not have to rely on the ingestion of a hallucinogen such
as ayahuasca, to uncover what Bresnick and Levin (2006) term
“profound alterations of temporal-spatial experiences including
expansive space and slowed time.” These experiences can be found
in long-term meditators. Whether the meditators in this study are
more aware of what Travis (1994) terms “an underlying, undif-
ferentiated field,” wherein presumably there is an alteration in
the experience of both space and time, is a metaphysical issue—
and not one that we can resolve using the present experimental
protocol. Nevertheless, as Hunt (2007, p. 226) has suggested,
“advanced meditation involves an attunement to a background
field of consciousness, whose increased meditative access seems to
be correlated with an unusually coherent EEG in the theta band-
width.” What might be considered to be the psychedelic effects
invoked by systematically observing (or, becoming sensitized to)
one’s experience of both space and time—sometimes resulting in
spacelessness and/or timelessness—might, in turn, be actually the
externalization of this background field of consciousness (Hunt
and Chefurka, 1976). We cannot make a conclusive case here
for this; we can, however, provide a portal for future research,
building on the protocol explored here.
MEG SOURCE LOCALIZATION ESTIMATES
“Then” and “There” (control) conditions, and their overlap
The “Then” vs. “Now” and “There” vs. “Here” contrasts served
as control conditions for ruling out autobiographic memory and
imagination processes, respectively, as well as attentional pro-
cesses, which might have taken place during the “Timelessness”
and “Spacelessness” target conditions. In both contrasts, only
increased theta activity was detected, mostly right-lateralized
(Tab l e s 3,4). Within the context of the hypothesis that time can
be represented along a left-to-right oriented mental time-line,
and based on psychophysical and neuroimaging studies, it has
been suggested that the right hemisphere entails the representa-
tion of the past and the left hemisphere the representation of the
future (Szpunar et al., 2007; Oliveri et al., 2009a). The right hemi-
sphere dominance in the “Then” vs. “Now” contrast is in line with
this, as participants were recalling past events.
Thetwocontrastsoverlappedinthreeclusters,whichincluded
four main regions: Right PPL, right precentral and MFG, and
bilateral precuneus (Figure 5,Tabl e 3 ). These results are in line
with fMRI studies of mental traveling to the past, reporting bilat-
eral PPL activation (Arzy et al., 2009) and left precuneus and
MFG activation (Szpunar et al., 2007). Moreover, the results sup-
port our hypothesis of episodic memory network activation in
the control conditions, as the right PPL and MPG were shown to
be involved in episodic memory performance (Rajah et al., 2011).
Similarly, the precuneus is a region involved with autobiographic
memory (Cabeza and Nyberg, 2000; Rugg et al., 2003), as well
as mental imagery (Lundstrom et al., 2003). Altogether, the over-
lappingpatternofthe“Then”vs.“Now”and“There”vs.“Here”
conditions reveals a largely right-lateralized network specialized
in episodic memory, as well as mental imagery of one’s body.
Alteration in the experience of time
The “Timelessness” vs. “Now” (Figure 4,Tab l e 2 )contrast
revealed theta activity in a right-lateralized network of parietal,
temporal and insular cortical regions, as well as the basal gan-
glia, thalamus and cerebellum. Specifically, these regions included
the motor areas (postcentral gyrus) spreading into supplementary
motor area—SMA (MFG), parietal lobule, thalamus, and basal
ganglia. This is consistent with previous prospective timing stud-
ies suggesting that fronto-striatal circuits consisting of recurrent
loops between SMA, basal ganglia and thalamus are critical for the
processing of duration (Coull and Nobre, 1998; Ferrandez et al.,
2003; Coull, 2004; Wittmann, 2009), as well as with neuroimag-
ing of temporal task performance documenting recruitment of
the right posterior parietal cortex (Coull and Nobre, 1998; Walsh,
2003; Oliveri et al., 2009a). Theta activity was also found in the
bilateral cerebellum, in accord with TMS (Tomlinson et al., 2013)
and PET (Coull and Nobre, 1998) studies showing a cerebellar
role in time perception and representation (Salman, 2002), as
well as over the right temporal gyrus, a region shown previously
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Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
Table 4 | Beamforming solutions for contrasts Then vs. Now and There vs. Here in the theta (4–8 Hz) frequency band.
Overlapped
conditions
Cluster
(no. voxels)
TLRC coordinates (mm, RAI) Hemisphere overlap Regions included in cluster (atlas TT_Daemon)
x y z L (%) R (%) Name Voxels
Then vs. Now
1 (87) −27.552.5 57.5 0 93 R. Superior parietal lobule 22
R. Postcentral gyrus 13
R. Inferior parietal lobule 7
2 (78) −42.57.5 52.5 0 70 R. Precentral gyrus 26
R. Postcentral gyrus 26
R. Middle frontal gyrus 11
3 (66) −32.517.5 17.5 0 100 R. Insula 34
R. Lentiform nucleus 11
4 (53) −12.567.5 32.5 1 92 R. Precuneus 36
R. Cuneus 14
5(15) 7.542.5 62.5 94 0 L. Precuneus 6
L. Paracentral lobule 4
6(14) −67.532.57.5 0 55 R. Superior temporal gyrus 10
R. Middle temporal gyrus 2
There vs. Here
1 (201) −62.57.5 12.5 0 90 R. Middle temporal gyrus 36
R. Superior temporal gyrus 27
R. Inferior temporal gyrus 20
R. Fusiform gyrus 18
R. Culmen 16
R. Postcentral gyrus 9
R. Cerebellar tonsil 6
R. Precentral gyrus 5
R. Parahippocampal gyrus 3
2 (129) 2.547.5 57.5 74 23 Cingulate gyrus 39
Paracentral lobule 34
Precuneus 29
Postcentral gyrus 7
Medial frontal gyrus 5
3 (66) −32.542.5 57.5 0 92 R. Superior parietal lobule 21
R. Precuneus 14
R. Inferior parietal lobule 11
4 (38) −37.512.5 52.5 0 74 R. Precentral gyrus 21
R. Middle frontal gyrus 15
5 (36) −12.5−32.57.5 0 100 R. Anterior cingulate 20
R. Caudate 8
Information supplied includes number of voxels in each cluster, center of cluster characteristics, hemispheric overlap, brain regions, and number of voxel s in the
region. Only clusters >2 voxels are presented. The Afni-supplied TT Daemon atlas was used. Due to poor resolution and signal leakage to non-brain regions, overlap
percen tages d o not always add up to 100%.
to be involved in time production in lesion (Noulhiane et al.,
2007) and TMS (Bueti et al., 2008) studies. Finally, theta activ-
ity was seen in the right insula, right somatosensory and bilateral
medial posterior cingulate cortices, a network involved in somatic
information processing. The interoceptive insula has been previ-
ously suggested to be responsible for the perception of duration
(Craig, 2009a,b; Wittmann, 2009; Wittmann et al., 2010). Indeed,
an fMRI study of MM practitioners showed that attending to
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Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
FIGURE 6 | Differences in theta activity between the BTS (n=5) and
NTS (n=6) groups over 4 overlapping ROIs. (A) Group ×Cluster
interaction. BTS, both time and space; NTS, Not both Time and Space; (B)
Spacelessness (top) and Timelessness (bottom) group theta differences
within the 4 clusters, calculated as BTS minus NTS. Color scale denotes
log(theta power) values. Left column—right superior temporal gyrus (STG);
Middle column—right posterior cingulated cortex (PCC); Right column—left
PCC and cerebellum clusters.
the present moment was accompanied by activation in the right
insula as well as the somatosensory cortex (Farb et al., 2007).
Altogether, the regions recruited during the “Timelessness”
condition were previously related to either momentary processing
of time, or interoception. This is in accord with our hypothesis
that alteration in the expereince of time is related to an altered
sense of body.
Alteration in the experience of space
“Spacelessness” vs. “Here” showed theta activity which was largely
bilaterally distributed, over several regions (Figure 4,Tabl e 2 ).
Activated regions included bilateral cerebellum—known to reg-
ulate balance via processing of vestibular information (Timmann
et al., 2010); bilateral parahippocampus, known to subserve spa-
tial computation and learning (Aguirre et al., 1996); and right
basal ganglia, sensitive to spatially-related behavioral conditions
(Lavoie and Mizumori, 1994). Additionally, bilateral tempo-
ral gyrus, left thalamus, right postcentral gyrus, MFG, bilateral
frontal cortices and right parietal lobule (IPL) were activated,
all related to space processing (Halligan et al., 2003; Hagler and
Sereno, 2006; Silver and Kastner, 2009). Additionally, the bilateral
PCC and a small portion of the right insula, both related to inte-
roception (Damasio and Meyer, 2009), were activated. Moreover,
the PCC is involved in processing vestibular information (Wiest
et al., 2004) supporting its major role in navigation of the body in
space (Vogeley et al., 2004; Vogt and Laureys, 2005).
FIGURE 7 | Theta activity differences between the BTS (n=4) and NTS
(n=5) groups over insula. (A) Group main effect. ∗p<0.05. BTS, both
time and space; NTS, Not both Time and Space. (B) Condition ×
Hemisphere interaction. R, right; L, left. (C) Group differences in theta
activity, calculated as BTS minus NTS. Color scale denotes log(theta power)
values.
FIGURE 8 | OBE participant activity in the ROIs. Mean log theta power
during the Timelessness and Spacelessness conditions, in the selected
ROIs.
Altogether, the regions showing theta activity during the
“Spacelessness” condition were previously related with some form
of spatial processing (summarized by Iacoboni et al., 1997), or
with interoceptive processing. This, again, is in line with our
hypothesis that the alteration in the experience of space is related
to an altered sense of body.
Shared alterations in the experience of time, space, and body
The “Timelessness” and “Spacelessness” conditions overlapped
in four clusters (Figure 4,Tab l e 3 ): bilateral cingulate cor-
tex/precuneus (PCC/Prc), right temporoparietal junction (TPJ)
and left cerebellum. In line with our hypothesis, this pattern of
theta activity was different from the overlap pattern between the
www.frontiersin.org December 2013 | Volume 4 | Article 912 |15
Berkovich-Ohana et al. Neurophenomenology of altered sense of time and space
control conditions of “There” and “Then,” which showed activity
in regions related to mental imagery and episodic memory. We
argue that this overlap pattern is predominantly related to alter-
ations in the experience of the body. Subsequently, we provide
support for this argument, relating the overlapping regions with
bodily processing.
The PCC/Prc plays a central role in consciousness (Cavanna
and Trimble, 2006) as these regions differentiate patients in
minimally conscious states from those in vegetative states
(Laureys, 2005; Vogt and Laureys, 2005; Vanhaudenhuyse et al.,
2010), and are deactivated during REM sleep, when partici-
pants experience vivid dreams (Alkire et al., 2008). In addi-
tion, these are key regions for bodily representation (Damasio,
1998, 1999; Damasio and Meyer, 2009) and vestibular process-
ing (Wiest et al., 2004). Importantly, the PCC/Prc overlap for
the “Timelessness” and “Spacelessness” conditions clearly dif-
fers from the left precuneus cluster found in the “There” and
“Then”overlap(seerelativeactivityinFigure 5), by being rel-
atively inferior, anatomically. A recent fMRI study of emotional
processing (Immordino-Yang et al., 2009) proposes a different
role for inferior and superior parietal medial cortex, suggest-
ing the first to be related to interoceptive processing, and the
second to musculoskeletal processing. Consistent with that emo-
tional processing study, our data suggest a functional subdivision
in the parietal medial cortex regarding spatio-temporal pro-
cessing. While the “There” and “Then” conditions overlapped
in a more superior position, strongly related anatomically with
the lateral parietal cortex (Parvizi et al., 2006), which is acti-
vated in episodic memory and imagination, the “Timelessness”
and “Spacelessness” conditions overlapped at an inferior posi-
tion, strongly related with interoception (Damasio and Meyer,
2009).
The caudate part of the STG is encompassed within the
temporo-parietal junction (TPJ). The TPJ is a multimodal associ-
ation cortex, integrating thalamic, visual, auditory, somatic, and
limbic areas (Decety and Lamm, 2007). It is also a key region
for multisensory body-related self-processing, related to a first-
person perspective; damage to this area can produce a variety
of disorders associated with bodily awareness (Blanke and Arzy,
2005). Recent findings emphasize the role of the right TPJ i