Other intact functions include visual space perception and visual identification of shapes, objects, and faces. Besides simple perception, akinetopsia also disturbs visuomotor tasks, such as reaching for objects and catching objects. When doing tasks, feedback of ones own motion appears to be important. Causes
Brain lesions
Akinetopsia may be an acquired deficit from lesions in the posterior side of the visual cortex. Lesions more often cause gross akinetopsia. The neurons of the middle temporal cortex respond to moving stimuli and hence the middle temporal cortex is the motion-processing area of the cerebral cortex. In the case of LM, the brain lesion was bilateral and symmetrical, and at the same time small enough not to affect other visual functions. Some unilateral lesions have been reported to impair motion perception as well. Akinetopsia through lesions is rare, because damage to the occipital lobe usually disturbs more than one visual function. Akinetopsia has also been reported as a result of traumatic brain injury. Transcranial magnetic stimulation
Inconspicuous akinetopsia can be selectively and temporarily induced using transcranial magnetic stimulation (TMS) of area V5 of the visual cortex in healthy subjects. It is performed on a 1 cm² surface of the head, corresponding in position to area V5. With an 800-microsecond TMS pulse and a 28 ms stimulus at 11 degrees per second, V5 is incapacitated for about 20–30 ms. It is effective between −20 ms and +10 ms before and after onset of a moving visual stimulus.
Treatment
Pain relief is administered concomitantly to the treatment of the primary disease causing tenesmus. See also
Encopresis
Constipation
Fecal incontinence

References
External links

MedlinePlus Encyclopedia: 003131