However she knew the object had changed in position, she knew the size of the cube, and she could correctly judge the distance of the cube in relation to other nearby objects. Inner and outer visual fields
Detection of movement in the inner and outer visual fields was tested. Within her inner visual field, LM could detect some motion, with horizontal motion more easily distinguished than vertical motion. In her peripheral visual field, the patient was never able to detect any direction of movement. LMs ability to judge velocities was also tested. LM underestimated velocities over 12 deg/s. Motion aftereffect and Phi phenomenon
Motion aftereffect of vertical stripes moving in a horizontal direction and a rotating spiral were tested. She was able to detect motion in both patterns, but reported motion aftereffect in only 3 of the 10 trials for the stripes, and no effect for the rotating spiral. She also never reported any impression of motion in depth of the spiral. In Phi phenomenon two circular spots of light appear alternating. It appears that the spot moves from one location to the other. Under no combination of conditions did the patient report any apparent movement. She always reported two independent light spots. Visually guided pursuit eye and finger movements
LM was to follow the path of a wire mounted onto a board with her right index finger. The test was performed under purely tactile (blindfolded), purely visual (glass over the board), or tactile-visual condition.
Inactivating V1 with TMS could induce some degree of akinetopsia 60–70 ms after the onset of the visual stimulus. TMS of V1 is not nearly as effective in inducing akinetopsia as TMS of V5. Alzheimers disease
Besides memory problems, Alzheimers patients may have varying degrees of akinetopsia. This could contribute to their marked disorientation. While Pelak and Hoyt have recorded an Alzheimers case study, there has not been much research done on the subject yet. Antidepressants
Inconspicuous akinetopsia can be triggered by high doses of certain antidepressants with vision returning to normal once the dosage is reduced. Areas of visual perception
Two relevant visual areas for motion processing are V5 and V1. These areas are separated by their function in vision. A functional area is a set of neurons with common selectivity and stimulation of this area, specifically behavioral influences. There have been over 30 specialized processing areas found in the visual cortex. V5
V5, also known as visual area MT (middle temporal), is located laterally and ventrally in the temporal lobe, near the intersection of the ascending limb of the inferior temporal sulcus and the lateral occipital sulcus. All of the neurons in V5 are motion selective, and most are directionally selective. Evidence of functional specialization of V5 was first found in primates. Patients with akinetopsia tend to have unilateral or bi-lateral damage to the V5. V1
V1, also known as the primary visual cortex, is located in Brodmann area 17.