PSY 2C 08: BRAIN, BODY AND
UNIT–I: BRAIN AND BEHAVIOUR
TOPIC: Body Scheme Disturbances
BODY SCHEME DISTURBANCES
Body scheme is the understanding of one’s body parts and their relative positions in space.
This is achieved via a complex process of integration of our sensory and motor systems. The
most commonly seen problems include the individual’s inability to recognise their right from
their left or an inability to identify parts of their body.
Problems with body scheme can impact on the person’s ability to engage in activities of daily
livings such as, difficulty in participating in and/or accuracy when brushing hair, shaving,
brushing teeth, dressing etc. and the person may be unable to respond to instructions to move
parts of their body e.g. asking the person to lift their right arm during washing.
General term for the personal awareness of one’s body, including the location and orientation
of its various parts and their relative motion in space and time, as well as its functional integrity.
Although usually taken for granted, to effectively carry out normal motor activities one needs
to appreciate both the static and kinetic state of the body as a whole as well as its individual
parts. This information is derived from a number of sensory feedback loops, including signals
from receptors in the muscles, tendons, ligaments and the skin (proprioceptive, kinesthetic, and
tactile information), the inner ear or vestibular sense (orientation, direction, and speed of
movement of the head), and vision. Perhaps as a result of collective experiences with such
discrete sensory input, it has been suggested that individuals eventually develop what might be
considered a superordinate sense of one’s own body, independent of its movement in space or
time. This knowledge, at least to some extent, transcends one’s own body and allows insights
into bodies in general. Because awareness of body schema is such a fundamental operation of
the central nervous system, it almost functions at a subliminal level. One is normally only aware
of its operation when it becomes dysfunctional.
Disorders of body schema, known as asomatognosias, can take on various guises. Although
relatively rare, autotopagnosia represents what might be considered the quintessential body
schema disturbance. This deficit involves difficulties in identifying body parts and/or
appreciating their relative relations to one another. Care should be taken to differentiate
asomatognosia from unilateral neglect or anomia. In the former, the deficit is restricted to one
side of the body; in the latter, difficulties with naming extend beyond just parts of the body.
More commonly, autotopagnosia is restricted to difficulty identifying individual fingers,
especially the middle three. The deficit is usually bilateral and will frequently involve not only
difficulties with regard to the patient’s own fingers, but also those of the examiner or pictorial
representations of a hand. Deficits are often found whether tested visually or tactually and
whether verbal or nonverbal (e.g., matching to a model) responses are required. Unilaterally
expressed deficits in finger recognition using only tactile stimulation likely reflect a more basic
Right –left orientation refers to the ability to identify the right and left sides of one’s own body,
and to identify the right and left sides of a person seated oppositely or in a photo/drawing. In
additionally necessitates both spatial and symbolic elements for successful performance.
Right-left disorientation describes confusions or inability to identify the right and left sides and
suggests a lesion in the parietal lobe. Individuals with RLD often demonstrate sparing of other
spatial concepts, such as up- down and front- back. RLD is one of the Gerstmann signs, and it
has been described most frequently in connection with at least some of the other components
of Gerstmann Syndrome (Gerstmann syndrome –is a rare neurological disorder characterized
by the loss of four specific neurological functions: inability to write (dysgraphia or agraphia),
loss of the ability to do mathematics (acalculia), the inability to identify one’s own or other’s
fingers (finger agnosia) and inability to make distinction between the right- left side of the
body) . Right – left disorientation may develop consequently to broader disturbances body
schema or language processing, but can exist as a fairly isolated symptom, suggesting that it is
useful to retain RLD as a meaningful neuropsychological entity. The most common neural
correlate of RLD is left parietal dysfunction.
Right- left disorientation is usually associated with left hemisphere and left parieto- occipital
damage. It occurs only extremely rarely among individuals with right cerebral injuries. In
generally, these patients have difficulty differentiating between the right and left halves of their
body of others. Right- left spatial disorientation is more associated with left rather than right
cerebral injuries, given the tremendous involvement the right half of the brain has in spatial
synthesis and geometric analysis. RLD makes demands on numerous cognitive abilities,
including auditory comprehension, verbal expression of the labels “Left” and “right”, short
term memory for the instructions, sensory discrimination and mental rotation.