PHYSIOLOGICAL RESEARCH • ISSN 0862-8408 (print) • ISSN 1802-9973 (online)
2017 Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
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Physiol. Res. 66 (Suppl. 4): S493-S500, 2017
Do Multiple Body Modifications Alter Pain Threshold?
A. YAMAMOTOVÁ1, P. HRABÁK1, P. HŘÍBEK1, R. ROKYTA1
1Department of Normal, Pathological and Clinical Physiology, Third Faculty of Medicine, Charles
University, Prague, Czech Republic
Received March 22, 2017
Accepted November 3, 2017
In recent years, epidemiological data has shown an increasing
number of young people who deliberately self-injure. There have
also been parallel increases in the number of people with tattoos
and those who voluntarily undergo painful procedures associated
with piercing, scarification, and tattooing. People with self-injury
behaviors often say that they do not feel the pain. However,
there is no information regarding pain perception in those that
visit tattoo parlors and piercing studios compared to those who
don’t. The aim of this study was to compare nociceptive
sensitivity in four groups of subjects (n=105, mean age 26 years,
48 women and 57 men) with different motivations to experience
pain (i.e., with and without multiple body modifications) in two
different situations; (1) in controlled, emotionally neutral
conditions, and (2) at a "Hell Party" (HP), an event organized by
a piercing and tattoo parlor, with a main event featuring a public
demonstration of painful techniques (burn scars, hanging on
hooks, etc.). Pain thresholds of the fingers of the hand were
measured using a thermal stimulator and mechanical algometer.
In HP participants, information about alcohol intake, self-harming
behavior, and psychiatric history were used in the analysis as
intervening variables. Individuals with body modifications as well
as without body modifications had higher thermal pain thresholds
at Hell Party, compared to thresholds measured at control neutral
conditions. No such differences were found relative to mechanical
pain thresholds. Increased pain threshold in all HP participants,
irrespectively of body modification, cannot be simply explained by
a decrease in the sensory component of pain; instead, we found
that the environment significantly influenced the cognitive and
affective component of pain.
Pain threshold • Tattoos • Piercing • Scarification • Body
A. Yamamotová, Department of Normal, Pathological and Clinical
Physiology, Third Faculty of Medicine, Charles University,
Ke Karlovu 4, 120 00 Prague 2, Czech Republic. E-mail:
Pain is defined as an unpleasant sensory and
emotional experience associated with acute or potential
tissue damage, or is described by such expressions. Pain
is always subjective.
Like any definition, this one has its limitations.
Pain, by definition, is unpleasant; however, there are
individuals who intentionally caused pain to themselves
without much suffering. In people with self-harming
behaviors, physical pain can release and/or ameliorates
mental tension or mental pain (Niedtfeld and Schmahl
2009). Deliberately induced pain may also help people
with dissociative disorders return from a dissociated state
to reality, or to escape from reality to a dissociated state
(Fishbain et al. 2001). Another category includes those
who voluntarily undergo pain during aesthetic changes to
the body, such as tattoos, piercings, and scarification via
cutting or burning.
Recent epidemiological data points to
an increasing trend not only in the incidence of self-harm
but also in the incidence of body modifications
(Montgomery and Parks 2001, Laumann and Derrick
2006, Stirn et al. 2006). The steepest increase has been
primarily seen among adolescents (Greydanus and Shek
2009). Although some associations have been found
between the frequency of ear piercing and borderline
personality disorders, these relationships were neither
significant nor specific (Mi 1990).
S494 Yamamotová et al. Vol. 66
The motivational aspects for body modifications
are many and diverse. Multiple body modifications are
often associated with those searching for identity, a desire
to be affiliated with a certain subculture, or as
a manifestation of a specific type of non-verbal
communication (Stirn et al. 2011). Additionally, those
associated with body modifications are often regarded as
having antisocial behaviors. Tattoos and piercings can
express personal endurance to overcome pain as well as
having an addictive character that might be linked to
activation of the endogenous opioid system (Wohlrab et
Although the number of people with body
modifications has significantly increased over the past
several decades (Kluger 2015, Breuner et al. 2017), there
have been no studies that test pain perception in these
individuals. Therefore, the objective of this study was to
compare pain threshold to thermal and mechanical stimuli
in groups with different motivations to experience pain,
i.e., (1) in control subjects without body modifications,
and (2) in subjects with multiple body modification under
two different conditions, (a) emotionally neutral and
(b) emotionally intense. We tested the hypothesis that
people with multiple body modifications have higher pain
thresholds than those without body modifications.
Participants and method
Pain threshold was measured in 105 participants
with different motivations to experience pain (with and
without body modifications) (48 women and 57 men,
mean age 26±8 years) under two different conditions. The
first part of experiment was conducted in familiar
environments. Control subjects without body
modifications (C N, mostly medical students and their
friends; n=18) were tested under standard laboratory
conditions; participants with body modifications (BM N,
employees of tattoo parlors; n=12) were tested in a tattoo
parlor setting. Both these groups were tested under what
they perceived as natural and emotionally neutral
conditions. The second part of experiment was conducted
in a more emotionally charged environment, i.e., at a Hell
Party (HP), which was characterized by the organizers as
"a slightly rougher party for enthusiasts of piercings,
tattoos, and other body modifications, as well as fans of
BDSM (Bondage, Domination, Sadism and Masochism)."
Volunteers for research participation were
recruited via internet advertisement in the program of
a Hell Party. In this environment, two groups of
volunteers were measured. One group consisted of
participants with multiple body modifications (BM HP,
n=45), and the second group consisted of those without
body modifications (C HP, n=30), but with an active
interest in the experiences of the first group.
Given that pain perception can be influenced by
factors other than the environment, volunteers at the
HP filled out an anonymous questionnaire, regarding
information that we considered relevant to the modulation
of pain perception. These factors included: (1) alcohol or
other substances that had been used prior to pain testing
(amounts were in the range 1-2 glasses of beer or spirits,
with none of the participants describing use/abuse of
other addictive substances), (2) prescription medication
use at the time of pain testing (results: hypnotics – 1,
antidepressants – 1, analgesics – 3, and antibiotics – 2),
(3) previous or current psychiatric history, (4) self-injury
behaviors (SIB), and (5) types of body modifications
(tattoos, piercings, or scarification). The group with body
modifications included those participants who had tattoos
on more than 18 % of the body surface (without other
types of body modifications) or those with lesser tattooed
area but in combination with another types of body
modifications (numerous piercings and/or scarification).
Demographic characteristics associated with the
intervening variables are shown in Table 1.
Testing of the pain threshold at a Hell Party took
place in an isolated space without the presence of other
participants, just like in a laboratory or tattoo parlor.
A portable pen-like thermal stimulator of our own
production, operating on the principle of heating the skin
with hot air in a range from 20-70 °C, was used to induce
thermal pain (Fig. 1). In all settings, the pain threshold
was measured on the dorsal aspect of the index, middle,
and ring fingers of the non-dominant hand. The tip of
thermal stimulator was located behind the nail bed.
An average of the three measurements was used in the
analysis. When the thermal stimulus reached threshold
intensity, participants turned the apparatus off using
a computer mouse. Mechanical pain threshold was
measured on the same fingers using an electronic
algometer (Somedic, Sweden), operating on an area of
one square centimeter generating pressures in a range
from 0-2,000 kPa.
2017 Body Modifications and Nociception S495
Table 1. Demographic characteristics for the subgroups defined by intervening variables.
Thermal pain (°C)
Pressure pain (kPa) 951±263 630±218 1021±127 664±119 950±366 751±242 983±325 922±349
Psychiatric history (N)
No 6 5 20 20
C N: control subjects without body modifications measured in neutral settings; BM N: subjects with body modifications measured in
neutral settings; C HP: control subjects without body modifications measured at a Hell Party; BM HP: subjects with body modifications
measured at a Hell Party; F: female; M: male. Data are presented as Mean ± SD.
Fig. 1. The thermal stimulator device.
Differences in pain thresholds among control
subjects and those with body modifications in two
different experimental conditions were analyzed using the
two-way ANOVA (four levels of factor group: 1st group
– control subjects without body modifications measured
in neutral settings (C N); 2nd group – subjects with body
modifications measured in neutral settings (BM N);
3rd group – control subjects without body modifications
measured at a HP (C HP); 4th group – subjects with body
S496 Yamamotová et al. Vol. 66
modifications measured at a HP (BM HP) and two levels
of factor sex: men and women) separately for thermal and
mechanical threshold. Where indicated, simple planned
comparisons were used in post hoc analyses. Differences
were considered significant if p<0.05.
Thermal pain threshold
A significant main effect of group (F(3,97)=12.04,
p=0.000001) indicated that both groups measured in
emotionally neutral conditions (with or without body
modifications) had significantly lower pain thresholds
than the two other groups, which were measured under
emotionally stimulating or intense conditions at the
HP (Fig. 2). In spite of the fact that these two neutral
conditions are different, they represented for our
participants their habitual environment.
Fig. 2. Gender and group differences in thermal pain threshold.
Abbreviations are the same as in Table 1. Vertical bars denote
0.95 confidence intervals; **** p<0.00001.
We observed a tendency toward lower pain
thresholds in women compared to men (F(1,97)=3.55,
p=0.06), but interaction of factors group x sex was not
significant (F(3,97)=0.22, p=0.88).
Pressure pain threshold
Contrary to thermal pain, sensitivity to pressure
pain did not differ between groups (F(3,97)=1.46, p=0.23).
A significant difference was found in factor sex
(F(1,97)=11.43, p=0.001) with lower pain thresholds in
women compared to men. Group x sex interaction was
also not significant (F(3,97)=1.2, p=0.31) (Fig. 3).
Fig. 3. Gender and group differences in pressure pain threshold.
Abbreviations are the same as in Table 1. Vertical bars denote
0.95 confidence intervals; * p<0.05 M vs. F.
Effect of intervening variables
Since 45 persons, from the total number of
75 participants at the HP, stated alcohol use prior to pain
testing, we analyzed the effect on pain thresholds
separately using ANOVA with factors groups (with and
without body modification) and alcohol intake.
Regarding thermal pain threshold, alcohol intake had no
significant effect (main effect of alcohol F(1,72)=2.98,
p=0.09) on either group of participants (group x alcohol
interaction F(1,72)=0.73, p=0.39). Regarding pressure pain
threshold, alcohol intake also had no significant effect
(F(1,72)=1.45, p=0.23), however, the effect on the two
groups were not the same (group x alcohol interaction
F(1,72)=4.7, p=0.03), i.e. pain threshold was increased in
participants with body modifications.
The effect of other intervening variables on pain
thresholds in the HP participants with body modifications
are summarized in Table 2.
In subjects with body modifications, thermal and
pressure pain thresholds were influenced by self-injurious
behavior (SIB) differently. SIB did not affect thermal
pain threshold (main effect F(1,41)=2.1, p=0.16) whereas
SIB decreased pressure pain threshold (main effect
F(1,41)=4.0, p=0.05). This effect was probably caused by
the larger number of women with self-injurious behavior
in this group.
Current psychiatric comorbidity was associated
with decreased thermal as well as pressure pain
thresholds (main effects F(1,41)=5.2, p=0.03 and
F(1,41)=5.74, p=0.02, respectively). Again, this effect
could have been caused by the larger number of women
in this group.
2017 Body Modifications and Nociception S497
With regard to the nature of body modifications,
thermal pain threshold was not influenced by any of them
(main effect of tattoo F(1,41)=0.98, p=0.32; main effect of
piercing F(1,41)=2.9, p=0.1, main effect of scarification
In contrast, pressure pain threshold was higher in
persons with tattoos compared with those without tattoos
(F(1,41)=8.38, p=0.006). However, scarification had the
opposite effect; scarified participants had lower pressure
threshold than those without scarifications (F(1,41)=3.99,
p=0.05). Piercing was not found to have any effect on
Table 2. Effect of intervening variables on heat and mechanical pain threshold in Hell Party participants with body modifications.
variable (IV) Yes No Yes No
of IV Sex
Alcohol Thermal 57.4±6.3 57.4±5.7 55.4±9.0 51.6±7.1 F=0.60,
Pressure 1,022±343 812±153 1,092±264 766±353 F=5.92,
SIB Thermal 60.3±5.0 56.8±6.2 55.3±8.8 51.7±7.4 F=2.06,
Pressure 880±154 1,006±351 754±363 1,076±264 F=4.04,
Thermal 45.6 58.0±5.6 49.1±2.6 54.6±8.8 F=5.19,
Pressure 551 1,004±317 604±249 1,010±324 F=5.74,
Tattoo Thermal 57.9±6.5 57.0±5.8 54.7±9.1 51.3±6.3 F=0.98,
Pressure 1,022±378 938±258 1,097±264 650±290 F=8.38,
Piercing Thermal 56.2±4.7 60.7±8.4 52.7±7.4 57.0±11.7 F=2.90,
Pressure 966±309 1,030±391 933±327 868±497 F=0.00,
Scarification Thermal 50.5±6.9 58.1±5.7 54.7±10.3 53.2±8.1 F=0.80,
Pressure 688±194 1,013±323 653±484 962±321 F=3.99,
Data are presented as Mean ± SD; significant differences are in bold; n.s. nonsignificant.
Effect of body modification on nociception
We expected that individuals repeatedly
undergoing body modifications to have higher pain
thresholds than subjects without body modifications and,
as such, it would be easier for them to tolerate pain in an
experimental setting. In both experimental conditions,
neutral and emotional, we found differences in
nociception among male and female participants. Gender
differences that were seen were more associated with
pressure than with thermal pain thresholds, with lower
thresholds observed in women, which is in agreement
with many other published studies (Lautenbacher and
S498 Yamamotová et al. Vol. 66
Rollman 1993, Fillingim 2000, Hashmi and Davis 2014).
Effect of environment
Regardless of whether participants at the HP had
or did not have body modifications, their thresholds for
thermal and pressure pain were similar. Thermal pain
thresholds in both groups measured at the HP were
significantly higher than in the corresponding groups
measured in a natural, less emotionally charged
environment, while no such differences were found in
pressure pain thresholds. Thermal and mechanical pain
sensitivity do not necessary have to correlate and
differences can depend on the types of nerve fibers
involved in pain transmission. C-fibers, which respond to
noxious heat, play a major role in heat sensation, whereas
A-fiber nociceptors are predominately heat and/or
mechanosensitive (Dubin and Patapoutian 2010).
Nociceptive stimulation of C fibers, triggered by thermal
stimuli, correlates well with pain sensation, however,
similar activation of C fibers caused by mechanical
stimulation, which also activates A beta
mechanoreceptors, does not necessarily produce any pain
sensation (Hees and Gybels 1981).
Increased pain thresholds among HP participants
can be explained by the influence of the emotionally
charged or intense HP environment, which was perceived
as an overall positive experience. Several experimental
studies have shown that positive emotions as well as
pleasant music can lead to pain reduction (Rhudy and
Meagher 2001, Villemure and Bushnell 2002, Roy et al.
2008, Dubnar et al. 2012). Therefore, the HP party, as
a body modification festival, with music and workshops
demonstrating different techniques represented for both
active and passive participants a very emotionally
stimulating experience, which could have motivated them
to exceed either their own borders or empathically share
the pain experiences of others as well as sharing the
emotional responses of others. Several fMRI studies have
shown that during subjective experiences “to feel
another’s pain” requires, at least partially, activation of
a mental representation of one’s own pain, which is
located mainly in the anterior cingulate and insular
cortices, i.e. structures involved in processing the
affective component of pain (Jackson et al. 2006, Zaki et
al. 2007). Recently, Loggia et al. (2008) showed that
empathy itself can alter the sensory component of pain.
Consumption of alcohol
Alcohol intake at the HP increased pressure pain
thresholds, but not the thermal pain thresholds, in those
with body modifications. Experimental results indicate
that pressure pain stimulation might be more sensitive at
detecting the pain-dampening effects of alcohol than
electrical stimulation, the cold pressor test, and von Frey
hairs (Horn-Hofmann et al. 2015). Since alcohol is
known to have anxiolytic and stress-dampening effects,
changes in pain perception might be attributable to
changes in emotional state (Sayette 1999), which might
be more responsive in participants with body
Effect of psychiatric history
Most works dealing with pain perception in
patients with a spectrum of psychiatric disorders have
described decreased pain sensitivity (Lautenbacher and
Krieg 1994, Blumensohn et al. 2002, Papežová et al.
2005). Contrary to this, we found that our participants
with a psychiatric diagnosis had reduced thermal and
pressure pain thresholds. This result should be interpreted
with caution considering the small number of subjects
and the prevalence of women in this subgroup.
Effect of scarification on pain threshold
We showed that persons with scarification had
a significantly reduced mechanical pain threshold. It could
be a manifestation of hyperalgesia, due to a previous
painful invasive technique. Among our participants,
scarification, with the cutting of strips of skin for later
formation of ornamental visible scars, probably represents
the most painful procedure. Due to the small number of
subjects with scarification, a physiological interpretation of
their response is rather difficult; however, similar results
were also obtained in participants with self-injury
behaviors, which most frequently involved cutting; this
could be explained by the similarity of techniques used
during scarification and SIB. Regardless of the
explanation, our results contradict many literature findings,
which describe increased pain thresholds in subjects with
SIB (Bunderla and Kumperščag 2015).
For people who deliberately self-injure, and thus
voluntarily induce pain, it is believed that the
neurobiological mechanism mainly involves
a dysfunction of the opioid system, and to a lesser degree
the serotonergic and dopaminergic systems (Stanley et al.
2010, Groschwitz and Plenar 2012). Many patients that
repetitively self-mutilate seem to have developed a kind
of addiction to the experience. The addiction appears to
be based on a rapid reward effect that could be associated
2017 Body Modifications and Nociception S499
with either an up-regulation of opioid receptors in the
central nervous system or they may suffer from
premorbid changes in the activity of endogenous opioid
system (Frecska and Arata 2002). The functions of opioid
and dopaminergic systems are critical in motivation and
analgesia. Since these systems interact with each other,
the anatomical substrates of pleasure and pain can be
considered as overlapping (Leknes and Tracey 2008).
One of the motivations of HP participants was to
watch BDMS practices. Even though we did not gather
information regarding participant masochistic behavior, we
cannot rule-out this behavior as motivation for attending
the HP. This behavior may also contribute to an increased
pain threshold. It has been experimentally demonstrated,
using fMRI, that brain areas activated in association with
masochistic behavior were involved in sensory-
discriminative processing rather than affective pain
processing, during receipt of painful stimuli delivered in
the context of masochism (Kamping et al. 2016).
In this study, we showed that subjects with
multiple body modifications did not differ in nociceptive
sensitivity from control subjects without body
modifications in control/neutral environments. When
subjects both with multiple body modifications and
control subjects without body modifications were tested
in emotionally charged/intense environment (i.e. at a Hell
Party) they also did not differ in nociceptive sensitivity.
The observation that participants with and
without body modifications measured at the Hell Party
had higher nociceptive thresholds than the corresponding
groups measured in neutral environment leads us to
conclude that increased nociceptive thresholds cannot be
simply explained by reduced sensory perception caused
by body modification. Instead it suggests that pain
threshold in our participants was top-down modulated via
affective and cognitive processes.
Conflict of Interest
There is no conflict of interest.
This study was supported by project PROGRES Q35 and
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