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Unilateral Neglect 1
Unilateral Neglect: Assessment and Rehabilitation
Unilateral neglect is a brain disorder that is seen in a number of people who have
experienced damage to one hemisphere of their brain. These individuals do not respond normally
to objects, stimuli, and people located to their contralesional side, (i.e., the side opposite of the
lesion site) (Danckert & Ferber, 2006; Heilman, Watson, & Valenstein, 2003). This paper will
discuss the symptoms and possible causes of unilateral neglect, as well as the diagnostic testing
and rehabilitation therapies that are currently available to individuals who suffer from this
disability. Lastly, three case studies relating to neglect will be introduced, in order to exemplify
and personalize the individual experiences relating to unilateral neglect.
Unilateral neglect is a neurological condition in which the person fails to respond to
stimuli in the contralesional hemispace, which cannot be explained by primary sensory or motor
defects (Kim et al., 2007; Kolb & Whishaw, 2003). It is seen most frequently in patients who
have experienced damage to the right hemisphere of the brain, usually due to stroke, but
sometimes neglect may coincide with a traumatic brain injury (Zillmer & Spiers, 2001).
However, in some cases, unilateral neglect may be temporary and reversible when it occurs in
conjunction with seizures, electroconvulsive therapy, and intracarotid sodium amytal testing
(Wada testing) (Kolb & Whishaw, 2003; Lezak et al., 2004; Wenman, Bowen, Tallis, Gardner,
Cross, & Niven, 2003).
Individuals who experience neglect typically do not respond to stimuli located to their
left side. For example, they may not eat the food on the left side of their plate, shave only the
right side of their face, fail to read words on the left-hand side of a page, or when asked to draw
an object they are only able to reproduce the right side (Lezak et al., 2004; Wenman et al., 2003).
Zillmer and Spiers (2001) point out that “in one respect, neglect can be thought of as a forgetting
or lack of conscious attention to the left side, but even more so--it is as if awareness is being
pulled to the right” (p.134). In extreme cases, Mesulam (1985) comments that “when neglect is
severe, the patient may behave almost as if one half of the universe had abruptly ceases to exist
in any meaningful form” (p. 142). Although unilateral neglect can occur after damage to either
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hemisphere, left-side neglect due to right-hemisphere damage is far more common, longer lasting
and severe than right-side neglect due to left-hemisphere damage (Danckert & Ferber, 2006;
Kleinman, Newhart, Davis, Heidler-Gary, Gottesman, & Hillis, 2007; Lezak et al., 2004).
Furthermore, research has indicated that the presence of neglect in stroke patients is considered
an adverse indicator of their prognosis for recovery (Wenman et al., 2003; Cassidy, Lewis, &
Gray, 1998).
In some cases, individuals with severe unilateral neglect fail to make eye movements
towards stimuli on the contralesional side. Instead, their eyes deviate towards the ipsilesional
side, (i.e., the side with the lesion) (Hillis et al., 2006; Ladavas & Zeloni, 1997; Mattingley &
Husain, 1998). However, the unilateral neglect response is not due to any loss of vision; instead
it is a cognitive inability to perceive what is in the visual field on the contralesional side.
According to Mesulam (1985), “neglect is not a defect of seeing, hearing, feeling, or moving but
one of looking listening, touching, and searching” (p. 142). Although neglect may be
demonstrated in more than one modality, it is usually confined to the visual performance,
indicating a significant relationship between spatial attention and movement (Hillis et al., 2006;
Punt & Riddoch, 2006).
Subtypes of Unilateral Neglect
Motor Neglect
Individuals who are suffering from motor neglect typically experience an absence of
spontaneous movement in the contralesional limb, which is not explained by damage to the
motor cortex (Hillis et al., 2006). For instance, when individuals are asked to raise both hands,
they frequently only elevate the ipsilateral hand to the lesion site (Punt & Riddoch, 2006). It is
important to note that motor neglect involves the contralateral side of the body and not the
contralateral environment, as is represented in the typical clinical presentation of unilateral
spatial neglect.
Neglect Dyslexia
People who are experiencing the symptoms of neglect dyslexia will characteristically fail
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to read the left part of sentences or single words (Hillis, Newhart, Heidler, Marsh, Barker, &
Degoankar, 2005). For example, “smile” is read as “mile” or “belief” as “grief.” Omissions
usually consist of the initial letter or substitutions of the original letter to form a grammatically
correct word. The opposite effect has also been reported with left hemisphere lesions (Lezak et
al., 2004). For example, “south” is read as “soup” or “modern” as “modest.” When asked to read
a complete sentence or a passage, patients often begin reading at the middle of the sentence and
read the entire passage in this manner despite the meaningless of the text (Hillis et al., 2005).
Neglect Dysgraphia
The symptoms of neglect dysgraphia usually involve a preference for the right page of a
document, which causes the individual to produce crowded handwriting with an inflated left
margin (Lezak et al., 2004). It is certainly not out of the ordinary for people with neglect
dysgraphia to have difficulty writing horizontally, as well as leaving large spaces between words
and committing graphic errors (Rode, Klos, Jacquin, Rossetti, & Pisella, 2006).
In both neglect dysgraphia and neglect dyslexia the pattern of errors may vary widely
between patients (Lezak et al., 2004). It is important to note that both conditions do not always
co-occur (Halligan & Marshall, 1993; Heilman et al., 2003).
Facial Neglect
People struggling with facial neglect show a defect in the recognition of normal faces and
in some instances only recognize half faces (Vuilleumier & Schwartz, 2001). Young, DeHann,
Newcombe, and Hay (1990) describe this as a domain-specific form of unilateral neglect. In their
research the deficit was present with the representation of both internal and external facial
features. Indeed, research indicated that the judgment of facial expressions and the resemblance
between faces also suffered from neglect. The authors believe this phenomenon occurs from a
failure to attend to the left side of faces, due to the injury of the right hemisphere that produces a
right-sided cognitive preference.
Auditory Neglect
Although a few studies have reported the presence of auditory neglect, it remains
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complicated to validate (Eramudugolla, Irvine, & Mattingley, 2007; Spierer, Meuli, & Clarke,
2007). This difficulty arises from the fact that the auditory system is not nearly as lateralized as
the visual system. Therefore, testing with unilateral stimuli cannot be accurately controlled. For
instance, past studies have utilized the presentation of bilateral auditory stimulus and defined the
failure to respond to the stimulus in the left hemispace as auditory neglect (Lezak et al., 2004).
Due to the bilateral nature of the auditory system, this form of neglect is often referred to as
inattention This type of deficiency in aural functioning is also known as extinction; however, it
has been argued that extinction is nothing more than an attenuated form of neglect (Punt &
Riddoch, 2006).
Related Disorders and Causation
Unilateral neglect has also been associated with a number of other disorders. These
include: (a) anosognosia--which refers to the loss of ability to recognize or to acknowledge an
illness or body defect (Appelros, Karlsson, & Hennerdal, 2007); (b) anosodiaphoria--an
awareness of the contralateral defect despite an apparent lack of concern about the impairment
(Morin, Thibierge, & Perrigot, 2001); (c) allesthesia or allochiria--a failure to detect unilateral
stimuli (Heilman et al., 2003); (d) extinction--a failure to identify both stimuli in the presentation
of bilateral simultaneous presentation (Heilman et al., 2003; Punt & Riddoch, 2006).
The area of the brain most commonly affected by unilateral neglect is the posterior region
of the inferior parietal lobe in the right hemisphere (Heilman et al., 2003; Lezak et al., 2004).
The condition has also been associated with damage to sub cortical structures including the
thalamus. These three areas are interrelated and believed to comprise an important "neural
circuit." Therefore, damage to any one of them may affect the functioning of the others (Kolb &
Whishaw, 2003; Rode et al., 2006).
There are two general types of theories regarding the cause of unilateral neglect
symptoms: Attention theories and representational theories (Heilman et al., 2003). Advocates of
awareness theories hold that individuals with unilateral neglect have damage to areas of the brain
that control attention orienting. For example, people with neglect focus their attention on the
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ipsilesional side of space and fail to shift their attention to the contralesional side of space,
thereby not noticing stimuli on that side. Some proponents of attention theories believe that
damage occurs to a neural circuit that generates saccadic (fast eye) movements, which are an
important component of visual attention. Advocates of representational theories believe that
patients are unable to "construct a complete mental representation" of space on the contralesional
side. In this case the damage is believed to be to a neural circuit that controls spatial
representation and conscious awareness in the brain. Within these two general theories, there are
a variety of opinions regarding the specific mechanisms and brain functions that account for the
symptoms seen in individuals with unilateral neglect, which can vary in severity and scope from
person to person (Humphreys & Riddoch, 1993; Punt & Riddoch, 2006; Rizzolatti & Berti,
1993). For example, different sensory modes (visual, auditory, and tactile) and spatial
dimensions (horizontal, radial, and vertical) can be affected to different degrees. In fact, neglect
symptoms may be task specific, which may create difficulty in individual awareness and therapy
(Appelros, Nydevik, Karlsson, Thorwalls, & Seiger, 2004; Lezak et al., 2004).
Assessment / Testing
The presence of visuospatial unilateral neglect can be detected using some simple
screening tests that are quickly and easily administered at the individual’s bedside. The most
common are line bisection, figure cancellation, figure copying, and representational drawing
(Heilman et al., 2003; Lezak et al., 2004). These are subtests of a standard neuropsychological
test battery called the Behavioral Inattention Test, which is commonly used to test for unilateral
neglect in people who have experienced brain damage (Jehkonen, Ahonen, Dastidar, Koivisto,
Laippala, & Vilkki, 1998; Ptarmigan & West, 2000).
Line Bisection Test
The line bisection test is the most widely used diagnostic test for unilateral neglect
(Lezak, et al., 2004; Rizzolatti & Berti, 1993). In its most common version, the individual is
presented with a thin long horizontal line drawn in the center of a piece of paper and asked to
bisect the line, either by pointing to the line's midpoint or by quickly making a mark across the
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line at its midpoint. Typically, persons with left-sided unilateral neglect bisect the line to the
right of the actual midpoint of the line. Likewise, right-sided neglect is associated with a leftward
shift in people’s mark from the midpoint. In either case, the distance from the actual midpoint
(called the displacement) is an indicator of the severity of the client’s neglect (Lezak et al., 2004;
Marshall, 1998).
Although there is a general consensus among clinicians that poor performance on the test
is a reliable indicator of the presence of unilateral neglect, its specific merits for showing the
severity or particular manifestations of neglect are less understood (Heilman et al., 2003; Lezak
et al., 2004). The test has been conducted using various line lengths, orientations, backgrounds,
and positions on the paper. Numerous studies performed by several researchers (as cited in
Halligan & Marshall, 1993), during the late 1980s and early 1990s, found that all of these
variables have "reliable effects on the measured severity of neglect" (Mozer & Halligan, 1997, p.
187). The effects of other individual and test administration factors on line bisection performance
have been studied to various degrees, individual age, reading habits (left-to-right or right-to-left),
viewing distance, gender, and handedness (i.e., whether the patient is left handed or right
handed).
Figure Cancellation Tests
In the cancellation tests, a person is presented with a piece of paper containing various
drawn figures, either short lines, letters of the alphabet, or stars scattered around the page (Lezak
et al., 2004). The patient is asked to draw a line through each figure on the page or, for the letter
test, through a particular letter. Typically, clients with left-sided neglect cross out figures on the
right side of the page and fail to notice the ones on the left side of the page (Cassidy et al., 1998).
Omission of more than 5 percent of the figures is considered the usual criterion indicating
unilateral spatial neglect (Mark & Heilman, 1998).
Studies have also indicated that there is a diagonal bias among unilateral neglect patients
during the performance of cancellation tasks. Mark and Heilman (1998) found that stroke
patients commonly indicate diagonal neglect (a corner-based spatial bias) on the cancellation
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tests, i.e., they omit targets toward one corner of the page, usually the bottom left quadrant.
The cancellation tests assess a client’s ability to ignore distracting stimuli and use visual
discrimination. Because letters are more complex and require greater control over information
processing, the letter cancellation test is considered the most demanding of the three tests and has
the greatest distraction factor (Cassidy et al., 1998).
Another visual inattention test with a high distraction factor is referred to as the balloons
test (Lezak et al., 2004). In this cancellation test, the patient must search and cross out particular
shapes scattered amongst a background of very similar and distracting shapes, viz., circles and
circles with a line adjoining (balloons). This test battery can distinguish between attention and
visual field deficits.
Figure Copying Test
In this test, the individual is asked to copy a simple drawn figure, such as a daisy (Lezak
et al., 2004). Clients with left-sided unilateral neglect typically copy only the right side of the
figure, leaving the left side of their drawing blank, unfinished, or distorted in some way. Ishiai,
Seki, Koyama, and Izumi (1997) found that unilateral neglect patients shown a complete drawing
of a daisy (a large central circle surrounded by many side-by-side smaller circular petals)
correctly identified the figure as a daisy and did not mention any missing petals. However, when
asked to copy the daisy, the patients consistently drew a daisy that was correct on the right side
only, with large gaps between petals on its left side. Interestingly, the same patients were able to
arrange a large circle and many smaller circles into the shape of a daisy, when asked specifically
to do that task.
Representational Drawing Test
In this test, the patient is asked to draw a simple diagram of a common object. A clock is
often used, because it requires the placing of numerals around the face (Ishiai, Sugishita,
Ichikawa, Gono, & Watabiki, 1993; Lezak et al., 2004). Patients with left-sided unilateral neglect
may confine their drawings to the right side of the paper and distort or even omit the left side of
the object in their drawings (Lezak et al., 2004).
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Rehabilitation
Research indicates that the symptoms of unilateral neglect will typically stabilize two
months after a stroke event (Heilman et al., 2003; Lezak et al., 2004). In some cases the
condition may resolve itself, however in most instances the effects are enduring. Unilateral
neglect has been associated with poor performance of daily motor activities, such as writing,
poor sitting balance, crossing the street, or recognizing an object that exits on the contralesional
side of the visional field. Studies have shown that as visual neglect improves so will functional
motor skills. Unfortunately, there has been less than an optimal response to the various therapies,
due to the inability to maintain the positive effects of the various treatments that are currently
available (Pizzamiglio, Guariglia, Antonucci, & Zoccolotti, 2006; Punt & Riddoch, 2006;
Wenman, et al., 2003).
The symptoms of unilateral neglect are heterogeneous, which may affect an individual’s
limb movement, vision, hearing, or balance. In some instances, the neglect may be task-specific,
such as the involvement of inattention to far away space when attempting to cross the street
(Lezak et al., 2004). Due to this neurological phenomenon, the rehabilitation programs are
various and typically involve a top-down or bottom-up approach to therapy. The top-down
technique focuses on improving both the perceptional and behavioral biases by stimulating the
individual’s higher cognitive levels, through such methods as visual scanning. The bottom-up
practice is an attempt at modifying the sensorimotor level by initiating passive sensory
stimulation, as is used in Transcutaneous Electrical Nerve Stimulation (TENS) (Appelros et al.,
2004; Punt & Riddoch, 2006; Rode et al., 2006).
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Constraint and Bilateral Therapies
Constraint – Induced Movement Therapy (CIMT) is a cognitive method of therapy that
involves the conscious protecting of the unaffected side as a means of training the contralesional
side to respond with increased normality (Punt & Riddoch, 2006). In contrast, Bilateral
Movement Training (BMT) encourages the individual to utilize the unaffected limb or body side
as a technique to effectively guide the affected bodily area. BMT was recently endorsed by the
Royal College of Physicians’ National Clinical Guidelines for Stroke.
According to the guidelines, these lower level cognitive exercises aid in the development
of bilateral activities that include coordination, postural control, and gait. However, studies have
indicated that this particular therapy is difficult when the individual is involved in bilateral
environmental conditions, such as crossing the street when road traffic is present. It is
hypothesized by many researchers that compensation by the individual’s ipsilateral side is
compromised due to the increased stimuli to which the person must respond in a more complex
environment (Punt & Riddoch, 2006).
Transcutaneous Electrical Nerve Stimulation (TENS)
TENS is a therapy that involves the application of nerve stimulation to the contralesional
side of the neck, in order to improve balance and restore a symmetric gait in people who
experience neglect. The TENS bottom-up therapy method has received contradictory scholarly
reviews, with regard to the technique’s effectiveness and client comfort.
According to Punt and Riddoch (2006), TENS has the ability to dramatically improve the
balance in people suffering from neglect. In addition, these researchers found that if clients
directed their vision towards the contralesional side during the treatment their gait showed a
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significant improvement in symmetry. Those researchers who favor TENS assert that balance is
enhanced by improving the activation of the neurological processor that is injured; thereby
allowing the undamaged side to function more efficiently. On the other hand, Wenman et al.
(2003) found clients who received electrical stimulation in combination with self-instructional
training showed no benefit from the treatment. In addition, the therapy was not well tolerated by
a least two of the participants. Further research by Pizzamiglio et al. (2006), suggested that
TENS has the ability to temporarily improve or worsen the condition of unilateral neglect.
According to Pizzamiglio et al, eight weeks of TENS treatment did not result in positive changes
for all participants who took part in their study.
Visual and Spatial Scanning
The procedures used for visual and spatial scanning therapy are considered to be higher
cognitive training that utilizes the top-down approach to treatment (Pizzamiglio et al., 2006). The
technique that is utilized encourages the client to actively and sequentially scan various parts of a
simulated visual field, in order to produce the answers to various questions. These inquiries may
include information pertaining to: Reading, copying, copying of line drawings on a dot matrix,
and figure description.
Pizzamiglio et al. (2006) found overall that the group benefited from the therapy;
however, individual differences were reported. It was hypothesized that treatment duration or
lesion size and dimension may have been factors in these recorded differences. Follow-up
interviews with the participants indicated improved scanning ability many months after the
therapy was discontinued. Throughout the treatment process the participants’ exhibited
significant attitude changes relating to their disability. For instance, when the clients noticed
improvement in their respective skills they became more aware of the deficit, which aided them
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in their ability to create compensatory tactics. In addition, the therapy allowed the clients to
actively participate in their rehabilitation process, which appears to contribute to their expressed
feelings of positive self-worth and efficacy. It is important to note that some of the clients who
were initially indifferent to the disability experienced some depression when they began to
understand the severity of their impairment.
Virtual Environment Training System
This newly developed bottom-up approach to therapy was created to assist those
individuals who suffer from the symptoms of unilateral spatial neglect (Kim et al., 2007). This
new technology aids the person in everyday tasks, such as crossing the street. The virtual reality
equipment encourages attention to the contralesional visual area by creating visual cueing. The
theory behind this system is to enable people with spatial neglect to use their ipsilateral site as
compensation for the injury demonstrated by the contralesional area. Through training this
technology has the ability to reduce asymmetry between the left and right side in cases of
unilateral neglect. In a three-month follow-up study, the positive effects of the training remained,
although there was a small degree of neglect symptom increase in some clients. It is
hypothesized that this method of training is more beneficial than the traditional therapies. For
instance, scanning therapy must be provided in a variety of living situations for the method not to
become task-oriented, which would inhibit the actual improvement of neglect. Conversely, the
virtual reality therapy permits flexible usage in the least restrictive environment, which aids the
client in using this method as a way of creating independence when performing the functions of
everyday life.
Prism Therapy
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According to recent research, Prismatic Adaptation (PA) may significantly reduce the
behavioral prejudices due to neglect, using a bottom-up process. Rode et al. (2006), used prisms
that displaced the visual field by 10° in a rightward direction. After a two to five minute
exposure to the prism the participants’ manual straight ahead pointing shifted significantly to the
left side. Prior to the prism therapy the participants were identified as manually pointing 9° to the
right, therefore there was a 70% compensation for the 10° optical displacement. Six of the clients
who were exposed to PA showed significant improvement in symptoms for both spatial and
object neglect. In addition, PA has been found to improve visual-spatial deficits, such as spatial
dysgraphia (right page preference, graphic errors, and failure to write horizontally), as well as
audio insufficiency. In fact, PA appears to aid in the ability to create and investigate symmetrical
inner representations.
Equally impressive is the length of improvement time that is offered by this therapy.
Research has indicated that a five-minute session lasts much longer than any other form of
therapy (e.g., two hours and one day respectively). In fact, there have been some case studies that
show a marked improvement for as long as four days. Further research has demonstrated that
repeated sessions of PA exposure, such as two times daily for a period of two weeks, will bring
about noteworthy improvement that lasts for a five week period (Rode et al., 2006).
Researchers are unsure whether PA is a recovery therapy or a form of selective
compensation. However, it is hypothesized that PA may activate the network between the
cerebellum, thalamus, and cortical areas of the brain, causing the positive effects of PA therapy.
More importantly, PA appears to be the only treatment that focuses on the right cortical
hemisphere, as opposed to the traditional training that stimulates the ipsilesional side of the brain
(Rode et al., 2006).
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Case Studies
Case Example One
Mr. L. is a seventy-seven-year-old, right-handed male, who was referred to the Kessler
Institute for Rehabilitation (KIR) for evaluation, following a verbal assault toward staff members
at a residential nursing facility, where he has resided for the past two years. Mr. L became
abusive during dinner when he claimed, “Everyone else is getting steak except me.” A review of
his medical records revealed that Mr. L. experienced a CVA (cerebrovascular accident) 12
months previously, with damage to the parietotemporal cortex (Brodman 39/40) and cingulate
gyrus, which caused Mr. L. to suffer from deficits in spatial awareness.
The nursing staff reported that this type of behavior was out of character for Mr. L; he
had never acted aggressively in the past. Mr. L. was administered a variety of
neuropsychological tests and it was apparent that he suffered from neglect. He scored below the
first percentile on tasks involving line cancellation, clock drawing, and hemi-attention. There is
also evidence of early dementia and he will be referred for a complete neurological and
neuropsychological evaluation.
Meanwhile, Mr. L. has to be assisted by staff in negotiating obstacles in his left visual
field. In addition, Mr. L. showed significant signs of anosognosia for the visual field deficits
until he was made aware of his difficulty. Through rehabilitation therapy Mr. L. will learn to
acknowledge the visual and spatial difficulties, which will enable him to strengthen his ipsilateral
side to compensate for the deficit in cognitive functioning from the lesion that is located in the
right hemisphere of Mr. L.’s brain (R. P. Conti, personal communication, October 3, 2007).
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Case Example Number Two
Mr. W is a 62-year-old married, right-handed, African-American male who was admitted
to KIR following his release from _______ hospital. Mr. W. is a physical education teacher who
suffered a fall during class from a CVA. Upon evaluation, he was wheelchair bound and alert,
but under aroused and sluggish in his responses to various stimuli. In addition, he complained of
a headache and fatigue. Mr. W. was oriented to both person and time but disoriented to place.
Mr. W. was only able to provide a partial explanation for his hospitalization and rehabilitation
(“I fell”). His previous medical history indicated that he suffered from hypertension and
experienced several head injuries from playing contact sports.
Throughout his neuropsychological evaluation, Mr. W. sustained attention for brief tasks.
His working memory was intact but he presented significant visual field deficits. Mr. W. is aware
of his difficulties but demonstrates impulsivity and a lack of understanding for safety precautions
(e.g., wheelchair seatbelt). He was referred to the cognitive remediation program, in order to
implement an approach to rehabilitation (R. P. Conti, personal communication, October 3, 2007).
Case Example Number Three
Ms. M. is a 71-year-old, right-handed, white female who was seen for neurobehavioral
assessment following her release from ______ hospital. She was admitted to the hospital
following a fall in her home. Family members reported changes in her behavior during the past
year. Her previous medical history was unremarkable. Ms. M. is a retired schoolteacher who is
widowed and lives alone. She complained to family members of “balance problems” during the
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past year. For example, she stated that when she was driving “cars come out of nowhere and pass
her.”
Ms. M. suffered a minor cerebrovascular incident (CVA) to the posterior right
hemisphere with a focal neurological deficit. She is aware of her condition and follow-up
neuropsychological testing has indicted minor neglect to the left hemi-space (R. P. Conti,
personal communication, October 3, 2007).
Discussion
The mysteries surrounding neglect are numerous, due to the heterogeneity of the
disability. For instance, it is not uncommon to have difficulty in diagnosing neglect because it is
often somewhat compensated for by the client, it may be modality specific, or its existence is
denied. Due to these complications, a full battery of testing should be implemented, so both the
client and therapist are able to recognize the disorder and its severity. In many cases, individuals
who suffer from neglect will respond accurately to unilateral stimuli while missing stimuli that is
contralesional during bilateral representations. This phenomenon in cognitive functioning may
encourage the client to not understand and recognize the issue as one of cognitive significance,
which can cause personal frustration and anger, which was illustrated by the case study of Mr. L.
From a clinical perspective, it is important for the clinician during the interview process to
recognize and appreciate the body movements of clients, as well as their ability to perceive
various stimuli when asked to concentrate on a specific task (Appelros et al., 2004; Punt &
Riddoch, 2006).
The signs of neglect are typically apparent two to four weeks after a CVA. Research
indicates that the disturbances of neglect are usually stabilized two months following the CVA.
Therefore, the time to properly assess for neglect would be at least two weeks after the stroke
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event. However, there appears to be no time constraints on assessment because neglect
symptoms do not seem to depreciate. It is important to note that some clients continue to decline
after the acute phase of neglect. Many researchers contend that this small difference in a
population of individuals with neglect may be due to continued silent infarcts, or persistent
cognitive decline, due to dementia. Of course, cognitive complications such these make any
sustained improvement in neglect therapy sub-optimal (Appelros et al., 2004; Pizzamiglio et al.,
2006; Wenman et al., 2003).
An example of this type of problem can be seen in the case of Mr. L. Mr. L. is suffering
from neglect, as well as continued dementia. In addition, Mr. L. is in denial of his neglect
deficiency, which has begun to cause him increased stress and agitation. Perhaps cognitive
scanning will aid Mr. L. in his ability to cognitively perceive his left hemi-space. If some
improvement in cognitive functioning is experienced by Mr. L., he will most likely begin to
understand his deficit, which will aid in the development of his compensatory behaviors and
improve his agitated emotional state.
In addition, prism therapy may be helpful if Mr. L. is unable to recognize the neglect
deficit. This approach will passively treat the inattention and allow for a higher level of
functioning in the area of neglect, while the dementia will continue. Lastly, it is important to
appreciate that Mr. L.’s continued cognitive decline can not be compensated for by neglect
therapy. Therefore there will be limitations to his progress, which must be addressed in his
comprehensive therapy program.
Due to the relationship between spatial attention and movement the symptoms of neglect
will affect both individual perception and action. This idea is exemplified by case number three,
which introduces Ms. M. and her inability to see traffic in her left hemi-space when driving her
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car. Ms. M. is aware of her disability and would largely profit from a form of therapy that will
increase her daily functioning.
If indeed there is minor neglect detected in Ms. M. she may find improvement through
the use of prism therapy. This therapy works from a bottom-up approach by passive sensory
stimulation. In this case, prism therapy would help Ms. M. in her ability to perform her daily
activities. In addition, this particular therapy offers an increase in the lasting effects of treatment.
Therefore, Ms. M. could receive therapy over a period of two weeks and reap the benefit for as
long as five weeks.
Cognitive scanning may also be utilized to aid Ms. M. This approach offers a top-down
design, due to the focus on higher cognitive stimulation. Again, Ms. M. who suffers from minor
neglect may benefit both physically and psychologically by participating in a therapy that is
based on client interaction and effort. This particular treatment has shown remarkable success,
and in a few cases of minor neglect, an improvement that lasted for months after therapy.
Ms. M. would possibly benefit from a therapy that is client motivated, due to her
understanding of the disability. This knowledge may encourage her to cultivate compensatory
behaviors that can be utilized within many living situations over time. Lastly, this treatment
allows Ms. M. to take control of the deficit, which will undoubtedly boost her self-esteem and
efficacy, due to the independence and self-pride that such a therapy has to offer.
In case number two, Mr. W. suffered both a CVA and past traumatic brain injuries from
contact sports. Neglect testing indicates that Mr. W. suffers from significant visual field
deficiencies. While this is undoubtedly true, it is important to understand that Mr. W. has also
presented behavior that indicates impulsivity, which must be evaluated in terms of the severe
head injuries and the CVA event. In addition, Mr. W. appears to be under aroused and sluggish,
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these indications of a blunt affect must be considered in his continued neurological testing and
rehabilitation program.
It is possible that Mr. W. would profit from virtual reality therapy. Virtual reality
rehabilitation is interesting because it allows Mr. W. more freedom than perhaps the other
treatments, because of the continued left hemi-space stimulation. Due to Mr. W.’s under aroused
state, sluggish response system, disorientation to place, and the physical immobility that he must
endure, the virtual reality system may provide the least restrictive treatment and environmental
benefit for practical everyday living.
Clearly, the symptoms and diagnosis of unilateral neglect are diverse and difficult; this is
mostly due to the disability’s homogeneity. A clinical interview and neurological testing are
imperative when the clinician and the client are deciding upon a treatment regime to rehabilitate
the symptoms of neglect. All clients must be assessed based upon their respective physiological,
psychological, and environmental conditions. Only then can a successful plan for rehabilitation
be established.
Unilateral neglect appears to be elusive in its ability to be successfully treated. However,
as technology advances so does the capacity to treat the symptoms of hemi-neglect. This is
supported by the technologies of both prism treatment and virtual reality therapy, which illustrate
how equipment and expertise can significantly alter rehabilitation options for the individual.
Although unilateral neglect is an old and frustrating disability the promise for advancements in
therapies are abundant, which allows hope, self-satisfaction, and self-sufficiency in everyday
living for people dealing with neglect.
This type of research is necessary for the clinician to understand how assessment,
changing technology, and individual circumstance may affect the rehabilitation of neglect.
Unilateral Neglect 19
Further examination is suggested to test various therapies, such as virtual reality, for the
effectiveness and duration.
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