Hemispatial Neglect - Presentation

Presentation

Hemispatial neglect results most commonly from brain injury to the right cerebral hemisphere, causing visual neglect of the left-hand side of space. Right-sided spatial neglect is rare because there is redundant processing of the right space by both the left and right cerebral hemispheres, whereas in most left-dominant brains the left space is only processed by the right cerebral hemisphere. Although most strikingly affecting visual perception ('visual neglect'), neglect in other forms of perception can also be found, either alone, or in combination with visual neglect.

For example, a stroke affecting the right parietal lobe of the brain can lead to neglect for the left side of the visual field, causing a patient with neglect to behave as if the left side of sensory space is nonexistent (although they can still turn left). In an extreme case, a patient with neglect might fail to eat the food on the left half of their plate, even though they complain of being hungry. If someone with neglect is asked to draw a clock, their drawing might show only numbers 12 to 6, or all 12 numbers on one half of the clock face, the other side being distorted or left blank. Neglect patients may also ignore the contralesional side of their body, shaving or adding make-up only to the non-neglected side. These patients may frequently collide with objects or structures such as door frames on the side being neglected.

Neglect may also present as a delusional form, where the patient denies ownership of a limb or an entire side of the body. Since this delusion often occurs alone without the accompaniment of other delusions, it is often labeled as a monothematic delusion.

Neglect not only affects present sensation but memory and recall perception as well. A patient suffering from neglect may also, when asked to recall a memory of a certain object and then draw said object, again, only draw half of the object. It is unclear, however, if this is due to a perceptive deficit of the memory (having lost pieces of spatial information of the memory) or whether the information within the memory is whole and intact, but simply being ignored, the same way portions of a physical object in the patient's presence would be ignored.