Neurocase
The Neural Basis of Cognition

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Potential relationship of self-injurious behavior to
right temporo-parietal lesions
Shaina Borah, Brice McConnell, Richard Hughes & Benzi Kluger
To cite this article: Shaina Borah, Brice McConnell, Richard Hughes & Benzi Kluger (2016):
Potential relationship of self-injurious behavior to right temporo-parietal lesions, Neurocase,
DOI: 10.1080/13554794.2016.1147586
To link to this article: http://dx.doi.org/10.1080/13554794.2016.1147586

Published online: 16 Feb 2016.

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NEUROCASE, 2016
http://dx.doi.org/10.1080/13554794.2016.1147586

REPORT

Potential relationship of self-injurious behavior to right temporo-parietal lesions
Shaina Boraha, Brice McConnella, Richard Hughesa,b and Benzi Klugera
Department of Neurology, University of Colorado Denver, Aurora, CO, USA; bDivision of Neurology, Denver Health Medical Center,
Denver, CO, USA

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a

ABSTRACT

ARTICLE HISTORY

Self-injurious behavior (SIB) is associated with several neurologic and psychiatric syndromes but rarely
with focal lesions. Two patients with lesions of the right temporo-parietal junction presented to
psychiatric inpatient services with SIB in the absence of notable neurologic deficits or suicidal ideation.
Right temporo-parietal lesions may be associated with disturbances of agency and body ownership,
both of which may facilitate SIB. Misoplegia, or hatred of a limb, may be associated with SIB and has
been reported without hemiplegia with a right temporo-parietal lesion. Further study is warranted to
improve our understanding of the mechanisms underlying SIB.

Received 15 April 2015
Accepted 22 January 2016

Introduction
Self-injurious behaviors (SIB) refer to a wide-range of behaviors
intentionally performed to harm one’s own body, typically in the
absence of suicidal ideation (Claes et al., 2010; Rao, Sudarshan, &
Begum, 2008; Winchel & Stanley, 1991). While uncommon in the
general population, these behaviors are described in several
psychiatric and pervasive neurological conditions, and are
pathognomonic for certain illnesses such as Lesch–Nyhan syndrome where they may be stereotyped and repetitive. When
present, SIB can contribute substantially to morbidity and mortality. SIB is less commonly described in association with focal
lesions and even more rarely as a presenting symptom
(Loetscher, Regard, & Brugger, 2006). SIB associated with focal
lesions may be reflective of disturbances of mood (i.e., depression), suicidal ideation, impulsivity, or altered bodily perceptions
including misoplegia, a syndrome characterized by hatred of a
limb which is often associated with self-injurious acts (Kishi,
Kosier, & Robinson, 1996; Loetscher et al., 2006; Pompili,
Venturini, & Campi et al., 2012; Stanley et al., 2010). Described
are two cases of SIB associated with focal strokes presenting
within a few years of each other. These cases both initially presented to psychiatric services for SIB and were notable for the
absence of suicidal ideation or focal neurologic deficits. They also
demonstrated striking similarities in terms of lesion location
(right temporo-parietal junction) with each other, and to a previously reported case of misoplegia presenting without hemiplegia which we have referenced in our discussion for
comparison (Loetscher et al., 2006).

Case 1
A 64-year-old man presented to medical attention after intentionally amputating his left hand with a circular saw in his
garage. When the man was questioned as to why he amputated his hand, he responded, “still trying to figure out why,”
and consistently expressed regret for having done so. The
CONTACT Benzi Kluger
© 2016 Taylor & Francis

Benzi.kluger@ucdenver.edu

KEYWORDS

Stroke; laterality; parietal
lobe; temporal lobe; selfinjurious behavior (SIB)

patient had experienced pain and numbness in the fingers
on his left hand, as well as mild left face numbness, since a
stroke that occurred 6 months prior to the amputation. Both
the man and his wife indicated that the patient believed the
pain in his left hand was a punishment for hitting his wife in
the past, but the patient had not expressed any desire for
amputation prior to the incident. The patient was stabilized
and admitted to the intensive care unit (ICU) for further
management.
The ICU team first consulted psychiatry regarding the
patient’s SIB, but the psychiatry team felt that primary psychiatric pathology was unlikely given the late age of onset and
requested a neurology consult. The patient had a history of
two strokes. The first occurred 3 years prior to the current
admission and was associated with several seizures and mild
speech problems and left-sided neglect, both of which
resolved within a few months. Notably, the patient also had
some neuropsychiatric symptoms following this stroke including hyper-religiosity with unusual behavior including baptizing himself in a river and being found in what appeared to be
an ecstatic religious experience in a neighbor’s yard. The
second stroke occurred 6 months prior to admission and was
associated with mild left face and hand numbness. Both
strokes were in right middle cerebral artery territory with
associated MRI findings of right temporo-parietal lobe injuries.
Prior to his amputation event, he was not thought to have any
additional psychiatric or neurologic pathology, and his neurological examination did not reveal focal deficits aside from left
hand pain/numbness and left face numbness. After the event,
his neurological exam was pertinent for left hand amputation
with re-attachment, as well as some impairment of left eye
vision which was suspected to be related to hypoperfusive
retinal ischemia in the setting of blood loss. Formal neuropsychological testing revealed cognitive deficits in recognition
memory, visual memory, visuospatial abilities, and construction ability; however, he did have intact verbal learning,

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S. BORAH ET AL.

abstract verbal reasoning, as well as testing of general safety
awareness. It is unclear when these cognitive deficits developed in relation to this amputation event, but it was speculated that blood loss due to the amputation may have
worsened prior cerebral ischemic injuries. Also of note, the
patient had possible hyper-religiosity around the time of the
event. He recalled a biblical verse entering his mind, either
before or shortly after the amputation, which was thought to
be (Mark 9:43): “If your hand causes you to stumble, cut it off
and throw it away.” An electroencephalography (EEG) was
performed and demonstrated slowing under the left parasagittal region, but did not demonstrate seizure or epileptiform
activity. MRI imaging revealed an old right temporo-parietal
junction stroke with no restricted diffusion to suggest an acute
infarction or significant recent seizure activity (Figure 1).

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Case 2
A 58-year-old woman was admitted to the ICU after consuming 16 ounces of bleach and then lacerating her neck. While
drinking the bleach, she claimed she had the thought “I
should drink some water because this is poison.” She then
began drinking water from a glass cup and when she accidently broke the cup proceeded to use the glass shards to
lacerate her neck. The woman described feeling detached
from herself during the incident and was unsure why she did
it. Five months earlier, the woman had used a knife to lacerate
her neck and her left wrist down to the bone. Notably, she
denied any suicidal ideation or planning around these incidents and described them as having a compulsive quality
where as soon as she saw the SIB instrument (e.g., the knife)

Figure 1. Self-injurious behavior (SIB)-related to right temporo-parietal lesions.
Lesion locations superimposed on MRI FLAIR image from case 1 (white) and
case 2 (black) presented for the first time in this article and Loetscher, Regard
and Brugger’s misoplegia without hemiplegia case (case 3; gray). [To view this
figure in color, please see the online version of this journal.]

she felt an immediate and strong need to use it on herself. She
had a history of depression, bipolar disorder and cognitive
impairment but no prior history of suicidality or suicide
attempts outside of these two events. The patient was
admitted to the ICU for medical stabilization and
management.
Again the ICU team initially consulted the psychiatry service regarding her SIB, but the psychiatry team felt that these
events were atypical for a psychiatric etiology given the dissociation between the acts and the apparent lack of suicidal
intent, and requested a neurology consult. The neurology
team found no focal findings on her neurologic exam and
recommended a brain magnetic resonance imaging scan
(MRI) and EEG. The patient had a normal awake and asleep
EEG. Results from the MRI demonstrated a lesion in her right
temporo-parietal region consistent with a small subacute
stroke, with apparent restricted diffusion in diffusion-weighted
imaging (see Figure 1). Neuropsychological assessment
revealed deficits in processing speed, verbal memory, and
visuospatial skills. Nevertheless, she demonstrated intact working memory, verbal recall, language skills, and executive functioning. Unlike the patient in case 1, she did not express any
hyper-religiosity or aberrant beliefs in relation to her SIB. She
was, however, thought to have ongoing depression by inpatient psychiatry.

Discussion
Both of the patients reported had focal neurologic lesions in
the right temporo-parietal junction presenting with SIB and no
focal neurologic examination findings. As SIB may encompass
a wide variety of actions, the similarities between the actions
of these patients merit review. Both patients presented with
behaviors of a compulsive nature, occurring without premeditated planning and seemingly impromptu in the moment.
There was a notable lack of suicidal intent. When unilateral
bodily targets were chosen (hand in case 1, wrist in case 2)
they were on the left side. These cases also exhibit some
similarities to the syndrome of misoplegia, that may occur in
the absence of hemiplegia with lesions in the right temporoparietal junction, and xenomelia, a syndrome characterized by
non-acceptance and a desire to amputate one or more limbs,
which has been recently associated with structural changes in
the right parietal lobe (Hilti et al., 2013). We hypothesize that
right temporo-parietal junction lesions contribute to SIB due
to this brain area’s critical role in networks related to the
maintenance of body ownership and agency. We further
hypothesize that due to disruption of these functions that
SIB associated with these lesions is more likely to be directed
at specific body parts and to have a quality of dissociation
from one’s body and less likely to be driven by mood or
suicidal thoughts. We will briefly review the normal functions
of the temporo-parietal junction and the results of lesions to
this area from the standpoint of potential relationship to SIB.
The right temporo-parietal junction contributes to networks important for several functions potentially relevant
to SIB including agency, body schema, moral cognition,
belief attribution, attention, and decision weighing (Döhnel
et al., 2012; Hétu, Taschereau-Dumouchel, & Jackson, 2012;

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NEUROCASE

Kahnt & Tobler, 2013; Krall et al., 2015; Young, Camprodon,
& Hauser et al., 2010). In looking at the functional networks
involving the right temporo-parietal junction, it may be
useful to consider those functions that would be expected
to inhibit or prevent SIB in healthy individuals. For example,
our sense of an integrated self includes body ownership,
which may be expected to inhibit SIB through protective
aspects of ownership, and agency, which may inhibit selfinjurious acts through a feeling of responsibility for one’s
actions (Feinberg, 2013). It is also expected that social
aspects of self and societal expectations of self-care may
also serve to inhibit SIB (Turner, Austin, & Chapman, 2014).
Lesions of the right hemisphere, particularly those involving
the temporo-parietal junction, are often associated with disturbances of attention, body schema and agency that may be
expected to facilitate SIB (Heilman, Watson, & Valenstein,
2013). For example, somatoparaphrenia is a disorder, which is
characterized by feelings of disownership toward limbs. It has
been hypothesized that somatoparaphrenia occurs due to
lesions in a network of the right fronto-tempo-parietal network
(Gandola et al., 2012). Xenomelia (or apotemnophilia) is a syndrome characterized by non-acceptance and an intense desire
for amputation of one or more limbs typically associated with a
sense of the limb as not belonging to them (hence, the term
xenomelia indicating hatred of something foreign; Hilti et al.,
2013). Notably, xenomelia is typically present from childhood
and is not associated with other neurologic or psychiatric
pathology. Like somatoparaphrenia, xenomelia appears to be
associated with right parietal dysfunction, based on magnetoencephalography and psychometric studies, as well as structural changes detected with MRI comparing cortical thickness
and surface area to control subjects (Brang, McGeoch, &
Ramachandran, 2008; Hilti et al., 2013; McGeoch, Brang, &
Song et al., 2011). As the first case presented following successful amputation of a limb, we may speculate that xenomelia, or
at least some characteristics of this syndrome, may have been
acquired as a result of his brain lesion. However, religious
delusions may have contributed to this patient’s act given his
prior history of hyper-religiosity, guilt for hitting his wife, and
quoting the bible in relation to this act.
Misoplegia is a condition in which a hemiplegic individual
feels negative feelings, often described as “hate” toward a limb
(Loetscher et al., 2006; Moss & Turnbull, 1996; Van Stralen, Van
Zandvoort, & Dijkerman, 2011). Patients with misoplegia typically abuse a limb verbally or physically. When occurring alongside hemiplegia, misoplegia may have indistinguishable
presentation between hate for the hemiplegia and inexplicable
negative emotions (Longo, Azañón, & Haggard, 2009). For
example, in a report of a young boy with misoplegia alongside
hemiparesis, the boy would intermittently switch from denying
his hemiparesis (anosognosia) and expressing hate toward his
limbs (Moss & Turnbull, 1996). In another report, a patient with
misoplegia verbally expressed hateful feelings and desires to
punish or hurt her arm post-stroke, yet the patient was found
stroking her arm affectionately when examined. The patient
explained that she was utilizing stroking as a method of maintaining her feeling of ownership over the arm (Longo et al.,
2009). Both of these misoplegia cases involved damage localized to the right temporo-parietal junction.

3

While misoplegia often occurs with hemiplegia, a case
report by Loetscher et al. (2006) describes misoplegia-like
symptoms in the absence of hemiplegia in a patient with a
tumor extending through her right temporo-parietal junction
(case 3 in Figure 1). There appears to be overlap in the right
temporo-parietal junction between this case and patients
reported here, which we have illustrated for comparison (see
Figure 1). Intermittently, their patient would switch from caressing her leg to cursing and physically abusing it. This peculiar negative attitude toward the body is compelling,
especially without hemiplegia. Alongside hemiplegia, one
might justify hate toward the body, due to paralysis making
the body unable to function properly. However, in a situation
where hemiplegia is absent, one may question what is driving
the expression of these negative feelings. Loetscher et al.
(2006) suggest that their patient had pre-morbid negative
feelings due to the leg being significantly shorter in length
than the right due to poliomyelitis. Following stroke or other
lesions, the ability of the patient to inhibit impulse and regulate emotion may be lost; releasing repressed hateful feelings
toward her limb. In the first case presented, it may be
hypothesized that underlying hand numbness and/or delusions about the hand may have been the source of hateful
feelings. In case 2, there were no specific bodily aberrations
involving targets of her hateful acts (left wrist, neck). It is
possible that underlying depression may contribute to more
generalized feelings of self-hatred leading to acts aimed at
harming the whole body (drinking bleach, lacerating the neck)
rather than a specific body area.
While SIB can be seen in epilepsy, as both ictal and postictal phenomena, neither of these cases had any evidence of
epilepsy by exam or EEG findings. However, SIB is more common in patients with epilepsy than in the general population
and may occur as a result of both ictal or post-ictal confusion
or psychosis, as well as psychiatric comorbidities (Meyer,
Voysey, Holmes, Casey, & Hawton, 2014). The occurrence of
injurious behavior and aggression appear bilaterally, and previous reports have found these behaviors alongside post-ictal
psychosis predominately with partial seizures emerging from
the temporal lobe, often involving the amygdala (Annan,
Bartolomei, Biberon, Cottier, & De Toffol, 2015; Hilger et al.,
2013; Nadkarni, Arnedo, & Devinsky, 2007). In a case involving
left temporal lobe epilepsy, a patient presented with selfmutilating behavior, guilty rumination, and persecutory behavior, raising the possibility that right hemisphere lesions associated with SIB may represent a release phenomenon (Shakya,
Shyangwa, & Pandey et al., 2010).
All three of these cases report what appears to be a detachment from their sense of self during their self-injurious incidents. It could be that disruption to a self-regulating system
involving the establishment of beliefs, decisions, prospection, or
theory of mind could be disrupted, creating disconnect
between the self and the experiences. Damage to the right
temporo-parietal junction may create a deficit in inhibitory
response and judgment, allowing negative affect toward the
body to be acted out. In case 1, the patient was reporting the
ideation of pain in his hand due to punishment for hitting his
wife in the past. The patient could be experiencing inability to
inhibit and regulate emotions toward his hand, possibly

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S. BORAH ET AL.

brought on by negative feelings toward his hand due to regretful past experiences. Similarly, the patient from case 2 was
diagnosed with major depressive disorder; it could be that
decreasing the ability to inhibit her negative emotions added
to her SIB. While these feelings may have been present prior to
strokes, they become amplified post-stroke.
Clearly the majority of patients with lesions involving the
right temporo-parietal junction do not present with SIB or
even misoplegia. In the cases reviewed above, it appears
that a predisposing factor such as disability of a limb (e.g.,
prior polio, hand numbness), abnormal thoughts such as delusions and hyper-religiosity, and/or a mood disorder can create
a priming for the episode of self-injury. Thus right temporoparietal injury may be hypothesized to release actions related
to these negative attributions, and remove normal inhibitions
that would otherwise prevent self-injurious acts with a compulsive and non-suicidal character. Indeed, the above cases
demonstrate, the SIB may occur in the setting of a temporary
state of mind, perhaps through via thoughts and emotions
beyond conscious awareness, leading to an apparently compulsive incident of SIB. Unfortunately, due to the clinical nature of these cases and a delay in recognizing their potential
links we did not pursue further neuropsychological or neurophysiological studies to confirm or refute our hypotheses.
Further studies of SIB may want to consider these qualitative
aspects when investigating the contributions of various brain
areas and networks to the etiology of these behaviors. These
cases also suggest that treatments aimed at increasing the
function of right hemisphere networks supporting agency and
body ownership may have promise in reducing certain types
of self-injurious acts.

Disclosure statement
No potential conflict of interest was reported by the authors.

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