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Remembering the Past to Imagine the Future: The Prospective Brain

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Remembering the Past to Imagine the Future: The Prospective Brain

Abstract

A rapidly growing number of recent studies show that imagining the future depends on much of the same neural machinery that is needed for remembering the past. These findings have led to the concept of the prospective brain; an idea that a crucial function of the brain is to use stored information to imagine, simulate and predict possible future events. We suggest that processes such as memory can be productively re-conceptualized in light of this idea.
© 2007 Nature Publishing Group
For more than a century, memory research
has focused on the past. Psychologists have
analysed the cognitive processes that allow
individuals to retain past experiences, and
neuroscientists have identified the brain
structures, such as the hippocampus, that
support this ability. A function of memory
that has been largely overlooked until
recently is its role in allowing individuals to
imagine possible future events. In this arti-
cle, we consider emerging evidence which
indicates that memory — especially episodic
memory — is crucially involved in our abil-
ity to imagine non-existent events and simu-
late future happenings. Indeed, brain regions
that have traditionally been associated with
memory appear to be similarly engaged
when people imagine future experiences.
We believe that such observations might
have far-reaching implications for concep-
tions of memory and its functions.
Memory for the future: background
In 1985, D. H. Ingvar published a paper
with the seemingly paradoxical title
“Memory for the future. According to
Ingvar, “concepts about the future, like
memories of past events, can be remem-
bered, often in great detail”
(REF. 1). Ingvar
summarized evidence which indicated that
regions within the prefrontal cortex have a
crucial role in the planning, foresight and
programming of complex action sequences
— examples of “memory for the future
(REFS 2–6). At approximately the same time,
E. Tulving argued that episodic memory,
which has traditionally been defined as a
memory system that supports remembering
personal experiences, allows individuals to
engage in “mental time travel” into both the
past and the future
7,8
. Tulving also claimed
that the capacity for mental time travel is
uniquely human
9
.
Perhaps as a result of this claim, much
research has focused on whether non-human
animals are capable of mental time travel
(for reviews, see REFS 10–12), using ingenious
demonstrations to question the claim for
human uniqueness. For example, there is
compelling evidence that food-caching
scrub jays can retrieve detailed information
about what food they have cached, as well
as when and where they cached it
10,13
.
Furthermore, recent work indicates that
jays can cache food in a manner that reflects
some form of planning for the future
14
that
is not simply a reflection of current
motivational needs
15
.
Debates about mental time travel in
non-human animals might never be set-
tled definitively, given that animals lack
the linguistic capacity to describe mental
contents. At the same time, research in the
child-development literature has investi-
gated the development of mental time travel
in children, and found that both episodic
remembering and future thinking emerge
relatively late in development, between
approximately three and five years of age.
However, similar issues regarding the ability
of young children to communicate their
mental contents have arisen
9,16,17
.
These issues have diverted attention away
from the relationship between future event
simulation and memory processes in humans.
During the past year, however, the growing
number of papers published on this topic
have changed this situation dramatically.
Insights from memory impairments
Early indications of a link between the
processing of past and future events were
provided by observations of patients with
memory impairments. In a seminal descrip-
tion of patients with Korsakoffs amnesia,
marked deficiencies in personal planning
were noted
18
. The amnesic patient K.C., who
showed a total loss of episodic memory after
a head injury, reported a ‘blank’ when asked
about his personal future or past
8
. (For
related observations, see REF. 19.)
Expanding on these observations, the
ability of five amnesic patients with bilateral
hippocampal damage to imagine novel expe-
riences was examined systematically
20
. The
patients were asked to generate everyday
imaginary experiences and were specifi-
cally instructed not to provide a memory
of a past event, but to construct something
new. Participants described their imaginary
scenarios, which were scored based on
their content, their spatial coherence and
their subjective qualities. The imaginary
constructions produced by four of the five
patients were greatly reduced in richness and
content compared with those of controls.
The impairment was especially pronounced
for the measure of spatial coherence, indicat-
ing that the constructions of the amnesic
patients tended to consist of isolated frag-
ments of information, rather than connected
scenes. It is important to note that this
study did not specifically require patients to
construct scenes pertaining to future events,
suggesting a more general deficit in the
patients’ ability to construct novel scenes.
The ability to remember the past and
imagine the future is also affected in
psychiatric disorders. A decade ago, a link
was reported between deficits in accounts
of past and future events in patients with
suicidal depression
21
. In response to word
cues, depressed patients showed less specific
retrieval of past events, and less specific
imagining of future autobiographical events.
Remembering the past to imagine
the future: the prospective brain
Daniel L. Schacter, Donna Rose Addis and Randy L. Buckner
Abstract | A rapidly growing number of recent studies show that imagining
the future depends on much of the same neural machinery that is needed
for remembering the past. These findings have led to the concept of the prospective
brain; an idea that a crucial function of the brain is to use stored information
to imagine, simulate and predict possible future events. We suggest that processes
such as memory can be productively re-conceptualized in light of this idea.
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PROGRESS
© 2007 Nature Publishing Group
A similar cueing procedure was recently
used to study past and future events in
schizophrenic patients
22
. Schizophrenics
recalled fewer specific past events and
imagined fewer specific future events than
did control subjects, but the schizophrenic
patients’ deficits were even greater for future
than for past events. Interestingly, this reduc-
tion in past and future specificity was corre-
lated with the extent of the patients’ positive
symptoms (delusions and hallucinations),
but not with their negative symptoms (such
as blunted affect). Other evidence correlated
positive symptoms in schizophrenics with
problems remembering contextual details,
suggesting that the patients’ impairments
on the past and future tasks reflect impair-
ments in accessing contextual details for the
purpose of constructing specific simulations
of their personal future or past.
A similar pattern was also recently
reported in healthy older adults, when they
were compared with college students
23
.
When asked to generate past and future
events, the older adults generated fewer
episode-specific details relating to the past
events than the younger adults, which repli-
cated earlier results
24
. Importantly, the same
effect occurred for future events: imagined
happenings also contained sparse episodic
information (TABLE 1).
The ability of older adults to generate epi-
sode-specific details of both past and future
events was correlated with their ability to
integrate information and form relationships
between items (relational memory). This
suggests that the simulation of future episodes
draws on relational processes that flexibly
recombine details from past events into novel
scenarios. Combined with other recent data
that indicate similar temporal distributions for
past and future events in older adults
25
, there
is now an empirical basis for proposing that
aging has parallel effects on both imagining
the future and remembering the past.
Insights from neuroimaging
Several recent neuroimaging studies have
directly contrasted situations where young
adults either recall from their own personal
pasts or imagine future events. These
studies have provided insights into three
central issues: whether common brain sys-
tems are used while remembering the past
and imagining the future, which specific
brain system(s) are used for imagining the
future, and the differences between the two
temporal directions of episodic thought.
In the first study, participants were
instructed to talk freely about either the near
or distant past or future
26
while a positron
emission tomography scan was carried out.
The scans showed evidence of shared activ-
ity during descriptions of past and future
events in a set of regions that included the
prefrontal cortex and parts of the medial
temporal lobe (namely the hippocampus and
the parahippocampal gyrus).
More recent studies have taken advan-
tage of the temporal resolution of functional
MRI (fMRI)
(BOX 1). In one study, partici-
pants were instructed to remember specific
past events, imagine specific future events
or imagine specific events that involved
a familiar individual (specifically, Bill
Clinton) in response to event cues
27
. Again,
there was striking overlap in the activity
associated with past and future events in
prefrontal and medial temporal regions, as
well as in a posterior midline region at or
near the precuneus. These regions were not
activated to the same extent when imagin-
ing events that involved Bill Clinton, which
demonstrates the existence of a neural
Table 1 | Examples of past and future events generated by older and younger adults
Age
group
Event
type
Cue
word
Event description
Non-episodic information Episodic information
Young Past Tree
…because I love cheese.”
“I went hiking in Muir Woods in California with my
boyfriend then and his room-mates … we went through
all these different ecosystems and you would see
different kinds of plants, so like we would see orchids
and I said, “Wow it’s so beautiful and it’s like wild”
that part was like a jungle: wet, very lush and green.
At the end of that trail, was like the beach so we
had bread and cheese and it was very fun and good
Young Future Oven None “I’m going to bake my first loaf of bread. Its going to be
probably Friday afternoon before Yom Kippur I’ll get
the recipe from an old cookbook… The room’s going
to be hot even though we have the windows open,
because we’re going to turn on the oven in the middle
of the summer. The light, bright kitchen light will be off,
and instead, we’re going to light a candle. BBC will be
on in the living room, it’ll be kind of static…
Older
Past Toy This reminds me of those toys that our grandchildren have.
I think they’re spoiled… Our son, the teacher, doesn’t have
a lot of money, and I think his wife is just can’t say no to the
kids. Every time she goes out, theres a toy coming homeI
generally will give my son money for specific things…
…Like he had a problem with his knee and I, so, to help
him with his doctors bill, I gave him some money, and
on the check I wrote,Dont spend on toys with this
check’.
Older
Future Engine In the next few years I hope we have an engine that doesn’t
have to use gas to run. I hope we come up with an alternate
source of energy to run vehicles. Because they’re a polluter,
and its getting to be very expensive to drive, and there’s a
lot of driver irritability over stop and go driving, having the
carbon poisoning happening
…The scene is I’m just driving along, in the Saab, and
not worrying about high energy costs…
Excerpts from event descriptions are from REF 23 (only a representative portion of the event description is shown here). Notably, older adults’ ability to generate specific
details did not correlate with the overall ability to generate information (as measured by verbal fluency).
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I remember taking a
daytrip last summer
and walking on the
beach.
I imagine picking
out a puppy at the
pet shop next year.
Cue
signature that is specific to the construction
of events in ones personal past or future.
Another fMRI study
28
experimentally
equated the level of detail and the related
phenomenological features of past and future
events. Tasks consisted of a construction
phase, during which participants generated
a past or future event, and an elaboration
phase, during which participants generated
as much detail as possible about the event.
The construction phase was associated with
common past–future activity in posterior vis-
ual regions and the left hippocampus, which
might reflect the interaction between visually
presented cues and hippocampally mediated
pointers to memory traces
29
. During the
elaboration phase, there was striking overlap
between the activity generated in the past
and future tasks in the prefrontal cortex,
medial temporal lobe regions including
the hippocampus and parahippocampal
gyrus, and a posterior midline region near
the precuneus. This study again reveals
strong evidence of overlap between the brain
systems that are used while remembering the
past and imagining the future.
Integrating the data from these three stud-
ies with related studies of autobiographical
memory
30,31
, it has been suggested that the
processes of remembering the past and imag-
ining the future are associated with a highly
specific core brain system
32
(FIG. 1). This core
brain system involves prefrontal and medial
temporal lobe regions, as well as posterior
regions (including the precuneus and the
retrosplenial cortex) that are consistently
observed as components of brain networks
that are important for memory retrieval
33
.
Detailed analyses of the interactions that take
place among the brain regions within this
core system further reveal that all of the com-
ponent regions are selectively correlated with
one another within a large-scale brain system
that includes the hippocampal formation
34,35
.
It thus appears that a brain system that
involves direct contributions from the medial
temporal lobe supports both remembering
the past and imagining the future.
In addition to this core brain system,
direct comparisons between imagining the
future and remembering the past consist-
ently reveal greater activity during episodic
thought about the future. Greater activity is
observed in frontopolar and medial tempo-
ral regions when the future is imagined than
when the past is remembered
26
. A direct
comparison of the activity that is associ-
ated with thinking about past and future
events
27
also identified several regions that
were significantly more active for thinking
about future events. In another study, the
early, constructive phase of future think-
ing revealed greater activity during future
conditions in multiple regions, including the
prefrontal cortex
28
.
It has been argued that this pattern
might reflect a more active type of imagery
processing that is required by thoughts of the
future but not of the past
27
. Others have pro-
posed that it might reflect the more intensive
constructive processes that are required in
order to imagine future events
36
. Both past
and future event tasks require the retrieval
of information from memory, and hence
both engage common memory networks.
However, only the future task requires that
event details gleaned from various past
events be flexibly recombined into a novel
future event. Thus, additional regions that
support these processes might be recruited
by the future event tasks.
The prospective brain
The evidence that we have considered
converges on the conclusion that the
process of imagining or simulating future
events depends on many of the same neural
processes that are involved in episodic
remembering. At the broadest level, these
observations provide an insight into the
adaptive functions of memory. The medial
temporal lobe system, which has long been
considered to be crucial for remembering
the past, might actually gain adaptive value
through its ability to provide details that
serve as the building blocks of future event
simulation.
Along these lines, the constructive epi-
sodic simulation hypothesis was advanced
36,37
.
In this hypothesis, the simulation of future
episodes is thought to require a system that
can flexibly recombine details from past
events. This idea was put forward in an
attempt to understand why memory involves
a constructive process of piecing together
bits and pieces of information, rather than
a literal replay of the past; the suggested
answer is that a crucial function of memory
is to make information available for the
simulation of future events. According to
this idea, thoughts of past and future events
are proposed to draw on similar information
stored in episodic memory and rely on similar
underlying processes, and episodic memory
is proposed to support the construction of
Box 1 | The typical paradigm for probing past and future events
The typical paradigm used in experiments that examine past and future events involves instructing
the participant to either remember a personally experienced event in their past or imagine a
plausible event in their future. Events are elicited by a cue word which might be a noun
28
(in the study
illustrated the cues were ‘beach’ or ‘dog’), an emotional word (such as ‘argument’ or ‘enthusiastic’)
21
or an event (such as ‘birthdayor ‘barbecue’)
27
. Transcriptions of events are then scored according to
the episodic specificity of the event produced (that is, whether the event is specific in time and
place)
21
and/or the types of detail that comprise the event (such as episodic details or other factual
information
23
; see TABLE 1). This general behavioural paradigm has since been adapted for functional
neuroimaging studies, in which a past or future event is silently remembered or imagined while lying
inside a functional MRI scanner (as depicted in the illustration) over a span of 10–20 seconds
27, 28
.
Subjective ratings of event phenomenology (such as vividness and emotionality) can be obtained
either during the scan or in the post-scan interview. Detailed descriptions of the events that were
generated in response to each cue shown during the scan are also obtained during the post-scan
interview, in order to confirm that an episodic event was successfully generated.
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Lateral temporal
cortex
Medial temporal
lobe
Medial prefrontal
cortex
Lateral parietal
cortex
Precuneus/
retrosplenial
cortex
future events by extracting and recombining
stored information into a simulation of a
novel event. The hypothesis receives general
support from findings of neural and cognitive
overlap between thoughts of past and future
events, and receives specific support from
recent research
38
in which college students
reported more vivid and more detailed future
event simulations when imagining events that
might occur within the next week in a famil-
iar context (their own or a friends home)
than in a novel context (a jungle or the North
Pole). Similarly, future events were more vivid
and more detailed when imagined in recently
experienced contexts (university locations)
than when imagined in remotely experienced
contexts (school settings). These results sup-
port the idea that episodic information is used
to construct future event simulations.
The constructive episodic simulation
hypothesis also receives specific support
from evidence that links hippocampal func-
tion and relational processing with future
event simulation: the hippocampal region
is thought to support relational processes
39
,
which are in turn suggested to be crucial for
recombining stored information into future
event simulations. One important issue that
needs to be addressed by further studies
concerns whether future event simulations
simply reflect the retrieval of parts or frag-
ments of prior episodes, or whether elements
from different episodes must be combined,
as proposed by the constructive episodic
simulation hypothesis.
Although the constructive episodic
simulation hypothesis emphasizes the
contribution of episodic memory to
future event simulation, it seems likely
that semantic memory also plays a
part. Semantic memory is the source of
knowledge about the general properties of
events, and it is presumably used to guide
the construction of future scenarios in
line with these known event properties.
Research that directly compares episodic
and semantic contributions to future event
simulations is needed.
It has been suggested that the core brain
system is also used by many diverse types
of task that require mental simulation of
alternative perspectives
32
. The idea is that
the core brain system allows one to shift
from perceiving the immediate environ-
ment to an alternative, imagined perspec-
tive that is based largely on memories of
the past. Future thinking, by this view, is
just one of several forms of such ability.
Thinking about the perspectives of others
(theory of mind) also appears to use the
core brain system
40
, as do certain forms of
navigation
20,32,41
.
An unresolved issue is the nature of the
information being processed when one
engages in forms of mental simulation that
depend on the core brain system. Buckner
and Carroll
32
suggest that an important
processing component is that the simulated
perception is of an alternative perspective
referenced to oneself — a process they
termed ‘self-projection
32
. After noting that
most of the tasks that activate the core brain
system require individuals to mentally con-
struct an alternative visual scene, Hassabis
and Maguire
42
recently suggested that
scene building’ is the common element.
Although the details of these ideas require
further exploration, both emphasize that
shifts along the temporal dimension (past
versus future) are probably not the vital
element. Adaptive constructive simulations
that use the core brain system might extend
to alternative perspectives of the present.
An important research task will be to assess
the contribution of temporal versus non-
temporal factors to the kinds of questions
highlighted here, and to determine whether
the activity of any component of the system
is modulated by temporal factors, such
as whether an event occurs in the recent
versus the remote future or past.
Whatever the outcome of such studies,
we believe that functional considerations
still mandate assigning a key role to the
specifically prospective features of the neural
and cognitive processes we have considered.
From an adaptive perspective, preparing for
the future is a vital task in any domain of
cognition or behaviour that is important for
survival. The processes of event simulation
probably have a key role in helping individu-
als plan for the future, although they are also
important for other tasks that relate to the
present and the past.
Given the adaptive priority of future plan-
ning, we find it helpful to think of the brain
as a fundamentally prospective organ that is
designed to use information from the past
and the present to generate predictions about
the future
43–45
. Memory can be thought of as a
tool used by the prospective brain to generate
simulations of possible future events. Such
a hypothesis calls for a shift of conceptual
emphasis, and even a change in methodol-
ogy. The time for taking the prospective
brain seriously appears to be at hand.
Daniel L. Schacter, Donna Rose Addis and
Randy L. Buckner are at the Department of
Psychology, Harvard University, 33 Kirkland Street,
Cambridge, Massachusetts 02138, USA; and the
Athinoula A Martinos Center for Biomedical Imaging,
Massachusetts General Hospital,
149 Thirteenth Street, Charlestown, Massachusetts
02129, USA.
Randy L. Buckner is also at the Center for Brain Science,
Harvard University and the Howard Hughes Medical
Institute, Fairchild Building, 7 Divinity Ave, Cambridge,
Massachusetts 02138, USA.
Correspondence to: D.L.S.
e‑mail: dls@wjh.harvard.edu
doi:10.1038/nrn2213
Published online 15 September 2007
Figure 1 | The core brain system that mediates past and future thinking. The core brain system
that is consistently activated while remembering the past
30,31,33
, envisioning the future
26–28
and during
related forms of mental simulation
32
is illustrated schematically. Prominent components of this net-
work include medial prefrontal regions, posterior regions in the medial and lateral parietal cortex
(extending into the precuneus and the retrosplenial cortex), the lateral temporal cortex and the
medial temporal lobe. Moreover, regions within this core brain system are functionally correlated
with each other and, prominently, with the hippocampal formation
34,35
.
We suggest that this core
brain system functions adaptively to integrate information about relationships and associations from
past experiences, in order to construct mental simulations about possible future events.
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Acknowledgements
The preparation of this paper was supported by grants from
the US National Institutes of Aging, the National Institute of
Mental Health and the Howard Hughes Medical Institute. We
thank A. Wong for invaluable aid with preparation of the
manuscript.
Competing interests statement
The authors declare no competing financial interests.
FURTHER INFORMATION
Daniel L. Schacter’s homepage:
http://www.wjh.harvard.edu/~dsweb
ALL LINKS ARE ACTIVE IN THE ONLINE PDF.
P R O G R E S S
NATURE REVIEWS
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NEUROSCIENCE VOLUME 8
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SEPTEMBER 2007
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661
... przyszłości, gdyż przypominanie sobie konkretnych wydarzeń z osobistej przeszłości również może stanowić ważne źródło informacji o sobie, które mogą być następnie projektowane w przyszłość. Twierdzenia te znajdują potwierdzenie w badaniach wykorzystujących metody neuroobrazowania, które wykazały, że podobne obszary mózgu są aktywowane zarówno podczas przypominania sobie jakichś osobistych wspomnień jak i wyobrażania sobie konkretnych przyszłych wydarzeń (Addis i in., 2007;Schacter i Addis, 2007). ...
... przyszłości, gdyż przypominanie sobie konkretnych wydarzeń z osobistej przeszłości również może stanowić ważne źródło informacji o sobie, które mogą być następnie projektowane w przyszłość. Twierdzenia te znajdują potwierdzenie w badaniach wykorzystujących metody neuroobrazowania, które wykazały, że podobne obszary mózgu są aktywowane zarówno podczas przypominania sobie jakichś osobistych wspomnień jak i wyobrażania sobie konkretnych przyszłych wydarzeń (Addis i in., 2007;Schacter i Addis, 2007). ...
... Odnosząc się do roli wykształcenia rodziców, można przewidywać, że bardziej wykształcone osoby są silniej nastawione na stymulowanie rozwoju swoich dzieci, także poprzez angażowanie je w dyskusje, podsuwanie inspirujących lektur, zachęcanie do ujmowania problemów z różnych perspektyw, czy też dzielenie się swoją rozległą wiedzą o świecie. A poziom wiedzy o świecie oraz zdolność do uwzględniania różnych możliwości są istotne dla trafności predykcji na temat własnej przyszłości i tworzenia jej symulacji (Schacter i in., 2007;Szpunar i in., 2014b). W rodzinach inteligenckich może też dochodzić do przekazywania wartości związanych z cenieniem własnego rozwoju i zdobywaniem wiedzy, co może skutkować tym, że dzieci pochodzące z tych rodzin będą częściej formować cele odnoszące się do edukacji. ...
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1) Aim of the research. The research problem was related to the role of prospective thinking for emerging adults’ development. The main subject of the study was the vision of one’s adult life, defined as the anticipation (Katra, 2008a), and, to be more precise, non-specific simulation of one’s future (Szpunar et al., 2014b). The main goals of the study were: a) explore the vision of one’s adult life in emerging adults, including describing its content, and structure and changes in this vision over time; b) investigating relations between the chosen factors and the vision of one’s adult life in emerging adults; c) verifying if these factors are predictors of changes in the vision on one’s adult life; d) analyzing relations between the characteristic of the vision of one’s adult life and identity development, and meaning in life; e) verifying if changes in this vision are related to changes in identity and meaning in life. 2) Material and method. This study was longitudinal. The second measurement was conducted 9-10 months after the first one. In the first measurement, 299 emerging adults aged 17 to 27 were recruited, and 177 of them also took part in the second part of the study. Due to the COVID-19 pandemic, data were gathered via the internet. Participants were asked to write about their predictions about their future, adult life. The adequately prepared judges coded these written answers. Data were gathered through standardized questionnaires (Dimension of Identity Development Scale [DIDS], Meaning in Life Questionnaire [MLQ], Portrait Values Questionnaire [PVQ-RR], Zimbardo Time Perspective Inventory [ZTPI], Future Time Perspective Questionnaire [FTPQ]) and extended sociodemographic survey. 3) Results. Results of the study indicate that emerging adults have moderately extended and detailed vision of their adult life. The most frequently represented (and mostly detailed described) aspects of life are work, intimate relationships, residence, and parenthood. The vision of one’s adult life seems to be stable over the last year of education in high school/ at university. The conducted analyses have revealed that vision of one’s adult life is at most moderately related to time perspective and life values. Additionally, various factors analyzed in this study seem not to be strong predictors of changes in the vision of one’s adult life. Another finding of this study is that forming a more extended and detailed vision of one’s adult life, stronger ease in recalling and describing it, and having a more positive emotional attitude toward it are related to having a more matured identity and higher meaning in life. Finally, it was observed that changes in the vision of one’s adult life (especially in the subjective attitude toward it) are related to changes in identity and meaning in life. 4) Conclusions. Many emerging adults can not predict their future, adult life, and developing its simulation. The vision of one’s adult life in emerging adults seems to be weakly related to life values, but in some aspects, it reflects stereotypes of gender roles. According to the findings of this study, it may be claimed that difficulties in developing the vision of one’s adult life may be the effect of poorly extended future time perspective, excessive focus on the present, and lack of engagement in identity development. Difficulties in achieving a matured identity may also 8 result from difficulties in developing the vision of one’s adult life. Gathered data indicate mutual relationships between the process of identity development and forming the vision of one’s adult life. The findings of this study shed light on the topic which was rarely explored before, which is forming the vision of one’s adult life—also concerning factors related to its development and the role of this vision for identity development and meaning in life. Results of this study may be applied to the youth’s mental health prevention, especially in the area of identity development.
... For defenses in philosophy, see(De Brigard, 2014a;McCarroll, 2018;Michaelian, 2011Michaelian, , 2016bSutton, 1998). For defenses in psychology, see(Addis, 2018(Addis, , 2020Schacter et al., 2007Schacter et al., , 2012). Barkasi, M., & Sant'Anna, A. (2022). ...
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The viability of a naïve realist theory of memory was a lively debate for philosophers of mind in the first half of the twentieth century. More recently, though, naïve realism has been largely abandoned as a non-starter in the memory literature, with representationalism being the standard view held by philosophers of memory. But rather than being carefully argued, the dismissal of naïve realism is an assumption that sits at the back of much recent theorizing in the philosophy of memory. In this paper, we identify three reasons why philosophers of memory have felt compelled to outright reject naïve realism. We argue that none of those reasons are successful. Thus, far from being a non-starter, we argue that naïve realism is a theoretical perspective that needs to be given serious consideration in current philosophy of memory debates.
... The canonical Default Mode Network (DMN), first described as the "default mode" of brain function , has been extensively linked to self-generated thought and mind wandering (Mason et al., 2007). The DMN has been defined as a set of core regions, including the medial prefrontal cortex and posterior cingulate cortex, that are engaged when individuals remember past experiences, imagine future experiences, or engage in related forms of mental simulation (Buckner, Andrews-Hanna, & Schacter, 2008;Schacter, Addis, & Buckner, 2007). Despite showing reduced activity during attentiondemanding tasks, DMN regions exhibit increased activation across a multitude of complex cognitive processes (Smallwood et al., 2021). ...
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Studies suggest that internally oriented cognitive processes are central to creativity. Here, we distinguish between intentional and unintentional forms of mind wandering and explore their behavioral and neural correlates. We used a sample of 155 healthy adults from the mind-brain-body dataset, all of whom completed resting-state fMRI scans and trait-level measures of mind wandering. We analyzed intentional and unintentional mind wandering tendencies using self-report measures. Next, we explored the relationship between mind wandering tendencies and creativity, as measured by a divergent thinking task. Finally, we describe patterns of resting-state network connectivity associated with mind wandering, using graph theory analysis. At the behavioral level, results showed a significant positive association between creativity and both intentional and unintentional mind wandering. Neuroimaging analysis revealed higher weighted degree connectivity associated with both forms of mind wandering, implicating core regions of the default network and the left temporal pole. We observed topological connectivity differences within the default network: intentional mind wandering was associated with degree connectivity in posterior regions, whereas unintentional mind wandering showed greater involvement of prefrontal areas. Overall, the findings highlight patterns of resting-state network connectivity associated with intentional and unintentional mind wandering, and provide novel evidence of a link between mind wandering and creativity.
... This network, whose constituent regions have undergone substantial developments in the course of human evolution 506,568 , was found to occupy a crucial position at the convergence of functional gradients of macroscale cortical organisation 495 , forming a structural and functional core of the human brain 208,544,548,569 , in line with its recently observed involvement in cognitive tasks [570][571][572][573] . In particular, the DMN is prominently involved in self-referential processing 574,575 , and 'mentaltime-travel' 576 or episodic memory and future-oriented cognition [577][578][579][580] . Its posterior regions in particular, act as relays between the neocortex and the hippocampal memory system 578 It is worth noting that the role of the FPN-DMN tandem in supporting consciousness has been suggested by Shanahan's hypothesis of a 'connective core' along the brain's medial axis 20 . ...
Thesis
Different perturbations of the brain’s delicate functioning, ranging from transient pharmacological interventions to severe trauma, can result in altered states of consciousness. To illuminate how the neurobiology and organization of the human brain support consciousness, we need to identify changes in brain function that accompany alterations in conscious state. However, the brain is a paradigmatic example of a complex system, raising the question: which aspects of its complex functioning and architecture should be the focus of our investigation? Traditionally, the quest for the “neural correlates of consciousness” has been framed in terms of spatial localisation: which brain regions are most relevant for consciousness? Complementing this extensive body of work, in my thesis I consider three alternative ways of conceptualising brain function (quantified from functional MRI), and how it may support consciousness. First, I adopt a time-resolved perspective, decomposing brain activity into predominantly integrated or segregated patterns of dynamic functional connectivity. Building on my previous work in anaesthesia and disorders of consciousness, I show how the dynamic interplay of functional integration and segregation is reshaped by the classic serotonergic psychedelic, LSD. Second, I consider a frequency-resolved perspective, decomposing functional brain activity into patterns of structure-function coupling across scales: the harmonic modes of the human connectome. This “connectome harmonic decomposition” of brain activity reveals a generalisable neural signature of loss of consciousness, whether due to anaesthesia or brain injury. A mirror-reverse of this harmonic signature characterises the altered state induced by LSD or ketamine. Connectome harmonics provide a robust indicator of consciousness across datasets, correlating with physiological and subjective variables. On the theoretical side, neuroscientific theories postulate that consciousness depends on the integration of information by a “global workspace” of brain regions. However, these accounts treat “information” as a primitive, whereas the recent framework of information decomposition has shown that Shannon information is actually a composite of several more fundamental kinds of information, including synergistic information, which is available only when a set of sources are considered jointly, and redundant information, which is available from multiple individual sources. Demonstrating the importance of disentangling these different kinds of information, I develop a framework for information-resolved analysis of brain activity, based on information decomposition. Combining functional and diffusion MRI, PET, and transcriptomics, I show that higher cognitive systems in the brain leverage the efficiency of synergistic information, whereas redundant interactions are predominantly associated with modular, structurally-coupled sensorimotor systems. Finally, by explicitly taking into account these fundamental kinds of information, I formalise the “global workspace” architecture in information-theoretic terms, revealing that both anaesthesia and disorders of consciousness induce a breakdown of synergistic integration in the brain’s Default Mode Network. Conceptually, these results contribute to reconciling two prominent theories of consciousness, the Global Neuronal Workspace Theory and Integrated Information Theory. Overall, viewing the brain as a time-, frequency-, and information-resolved complex system offers fruitful new ways to understand the brain’s functional architecture, laying the foundations to map the rich landscape of human consciousness.
... The manner memory is kept up-to-date is nevertheless only one of the two directions this work investigates. Recent studies highlight that the episodic memory also plays a key role in the mental simulation of future events [22], [23]; in other words, previously learned concepts influence our expectations about the future. We try to replicate this effect in our CL algorithm by further devising a future prepara-tion strategy: i.e.; a technique that exploits past and present data to prepare future classification heads to accommodate meaningful information. ...
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... In particular, our findings suggest that POE is underpinned by network level pathology rather than localised structural deficits [10] -an idea that is well-established in the schizophrenia literature [24,31,52,53]. An obvious extension of our work would be to examine whether these structural cortical changes are reflected in altered brain function within the default mode network and cognitive control network using functional MRI and neuropsychological measures of cognitive control, and default mode network functions such as verbal and visual memory, autobiographical recall, and prospective memory [26,54]. ...
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AND KEY WORDS Objective To explore the cortical morphological basis of the psychoses of epilepsy. Methods Psychosis of epilepsy (POE) has two main subtypes - postictal psychosis and interictal psychosis. We used automated surface-based analysis of magnetic resonance images to compare cortical thickness, area, and volume across the whole brain between: (i) all patients with POE (n = 23) relative to epilepsy-without psychosis controls (EC; n = 23), (ii) patients with interictal psychosis (n = 10) or postictal psychosis (n = 13) relative to EC, and (iii) patients with postictal psychosis (n=13) relative to patients with interictal psychosis (n=10). Results POE is characterised by cortical thickening relative to EC, occurring primarily in nodes of the cognitive control network; (rostral anterior cingulate, caudal anterior cingulate, middle frontal gyrus), and the default mode network (posterior cingulate, medial paracentral gyrus, and precuneus). Patients with interictal psychosis displayed cortical thickening in the left hemisphere in occipital and temporal regions relative to EC (lateral occipital cortex, lingual, fusiform, and inferior temporal gyri), which was evident to a lesser extent in postictal psychosis patients. There were no significant differences in cortical thickness, area, or volume between the postictal psychosis and EC groups, or between the postictal psychosis and interictal psychosis groups. However, prior to correction for multiple comparisons, both the interictal psychosis and postictal psychosis groups displayed cortical thickening relative to EC in highly similar regions to those identified in the POE group overall. Significance The results show cortical thickening in POE overall, primarily in nodes of the cognitive control and default mode networks, compared to patients with epilepsy without psychosis. Additional thickening in temporal and occipital neocortex implicated in the dorsal and ventral visual pathways may differentiate interictal psychosis from postictal psychosis. A novel mechanism for cortical thickening in POE is proposed whereby normal synaptic pruning processes are interrupted by seizure onset.
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Chapter
The chapter tackles the placement of self-reflective consciousness amongst the numberless gradations by Darwin. Discussions of self-consciousness inevitably lead to Descartes' dictum, "I think, therefore I am". The goal is a rapprochement between this view and the Cartesian view, emphasizing this kind of consciousness applicable only to humans. Descartes maintained that animals are unable to engage in self-reflection. Negative results of various ape language projects and broad advances in animal cognition suggest that Descartes was right about the uniqueness of language but that he was wrong about animal's capacity for thought and self-reflection. There is abundant evidence that nonhuman pirates can form representations and use them to solve problems. The concept of autonoetic consciousness, as Tulving calls it, seemed close to the construct of self-reflective consciousness and metacognition which was the concern. Thus, instead of focusing on language, more fundamental capabilities are considered-the origins of self-reflective consciousness.
Chapter
This chapter sets the stage for the rest of the book, presenting anatomical and clinical distinctions that serve as organizational and memory "hooks" for reading many of the other chapters. It discusses how massive damage to the frontal lobes can cause dramatic changes in personality and comportment while keeping sensation, movement, consciousness, and most cognitive faculties. It addresses questions such as: Is there a unitary "frontal lobe syndrome" encompassing all signs and symptoms? Are there regional segregations of function within the frontal lobes? Is it possible to identify a potentially unifying principle of organization which cuts across the heterogeneous specializations attributed to the frontal lobes?.
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This article examines the effects of memory loss on a patient's ability to remember the past and imagine the future. We present the case of D.B., who, as a result of hypoxic brain damage, suffered severe amnesia for the personally experienced past. By contrast, his knowledge of the nonpersonal past was relatively preserved. A similar pattern was evidenced in his ability to anticipate future events. Although D.B. had great difficulty imagining what his experiences might be like in the future, his capacity to anticipate issues and events in the public domain was comparable to that of neurologically healthy, age-matched controls. These findings suggest that neuropsychological dissociations between episodic and semantic memory for the past also may extend to the ability to anticipate the future.
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The author regrets that there was a mistake in reference [37] in the above article. The correct reference is:Oliva, A. and Torralba, A. (2001) Modeling the shape of the scene: a holistic representation of the spatial envelope. Int. J. Comput. Vis. 42, 145–175.The author sincerely apologizes for any problems that this error may have caused.