Brain injury effects
Sensory & perceptual problems after a brain injury
Sensory and perceptual
problems can arise from damage to the right side of the brain or
the parietal and occipital lobes of the brain.
These areas of the brain process the input from our senses. For
example, when eating an our apple our brain will report on the
- touch (it's round and smooth)
- sight (it is red)
- sound (it's crunchy)
- smell (the apple is fresh)
- taste (it's sweet and ripe).
Brain disorders such as traumatic brain injury (TBI) can disrupt
our senses, and also how our perception of what our senses tell us.
Our sensory and perceptual systems include:
- auditory (sound)
- visual (colour, shape, size, depth and distance)
- tactile ( touch relating to pain, pressure and
- olfactory (smells)
- gustatory (taste).
While problems can occur with our sensory systems, visuo-spatial
problem are often more noticeable. Possible issues include:
- drawing objects
- recognizing objects (agnosia)
- telling left from right
- mathematics (discalculia)
- analyzing and remembering visual information
- manipulating or constructing objects
- awareness of the body in space (e.g. climbing stairs)
- perception of the environment (e.g. following directions).
A well known problem is neglect where the brain ignores
one side of all it perceives - usually the left hand side. For
example, a person may ignore food on the left side of a plate or
fail to copy aspects on the left side of a picture.
Case study -
Elsie: Elsie was a 52 year old woman who had a
stroke three years ago and since then had problems with
side-swiping parked cars and posts on the left side of her car.
Elsie visited her doctor to have here eyesight checked. She was
referred to a neuropsychologist who diagnosed the problem as
left-sided neglect. When asked how she managed to drive, Elsie said
she stayed in the left lane and would know to steer right when she
heard her tires going off the road.
Prosopagnosia is a less common example of neglect - the ability
to recognize faces is affected, or even lost completely. In extreme
cases, there is an inability to distinguish one face from another
or read facial expressions (aperceptive
prosopagnosia). These people must rely on things like the
voice, hairstyle or clothing to identify others.
Case Study - Lincoln: After a
car accident Lincoln could not even recognize a photo of himself.
If separated from his family in a large crowd he cannot find them
again. One of the biggest problems he faces is that others cannot
understand his ability to see and recognize objects, but not other
Managing visuo-spatial problems
As shown with Elsie, neglect may be undiagnosed despite safety
issues. A person with neglect may be unaware of their problems, or
blame the problem on something else. It is important to identify
problems like neglect during rehabilitation and then educate the
person to increase their awareness of the impact of the problem in
Retraining skills is one way to manage
visuo-spatial problems until the person regains the required skill
as far as possible. Retraining usually involves repetitive and
intensive exercises for a specific skill or task e.g. practice at
drawing an object while receiving feedback. It tends to be more
effective with specific skills.
Changing the environment or expectations
involves modifying the environment to provide more support, or
reduce the demands of a particular skill. For example, support
could be fitting a handrail to make climbing stairs at home easier.
Reducing the demands of a skill can be as simple as just shifting
furniture at home so that walking around the house is easier. The
person may also learn to adjust their expectations and educate
other people about their difficulties.
Compensatory strategies are very
important in rehabilitation - they compensate for what a person has
trouble doing after a traumatic brain injury or similar brain
disorder. For example, Elise may be taught to turn her head
or body to scan the environment properly due to her neglect of
things on her left side.
A range of specialized equipment is available to fit into a
person's home or assist with community access.
External prompts are things like colour stickers for object
recognition, bright lights on the floor, musical or sound prompts,
stencils or transparent paper for copying, hand rails and other
A compensatory strategy for failing to recognize objects could
involve the person relying more on other senses such as touch,
hearing and smell by shutting their eyes.
The rehabilitation strategies described may be developed by a
neuropsychologist, occupational therapist or physiotherapist. The
eventual goal of any rehabilitation program greater independence
and use of self-management strategies. However, family members,
friends and support workers can still provide valuable support.
References and further information