Case studies

Potzl and Redlich's patient

In 1911, Potzl and Redlich arise a 58-year-old changeable accommodating with mutual accident to her after brain.1 She declared motion as if the article remained anchored but appeared at altered alternating positions. Additionally, she aswell absent a cogent bulk of her beheld acreage and had anomic aphasia.

editGoldstein and Gelb's patient

In 1918, Goldstein and Gelb arise a 24-year-old macho who suffered a gunshot anguish in the after brain.1 The accommodating arise no consequence of movement. He could accompaniment the new position of the article (left, right, up, down), but saw "nothing in between".1 While Goldestein and Gelb believed the accommodating had damaged the crabbed and centermost locations of the larboard occipital lobe, it was after adumbrated that both occipital lobes were apparently affected, due to the bilateral, concentric accident of his beheld field. He absent his beheld acreage aloft a 30 amount aberration and could not analyze beheld altar by their able names.1

edit"LM"

Most of what is accepted about akinetopsia was abstruse from LM, a 43-year-old changeable accepted into the hospital October 1978 accusatory of cephalalgia and vertigo.5 LM was diagnosed with occlusion of the aloft sagittal atrium which resulted in bilateral, balanced lesions after of the beheld cortex.5 These lesions were absolute by PET and MRI in 1994.2 LM had basal motion acumen that was preserved as conceivably a activity of V1, as a activity of a "higher" adjustment beheld cortical area, or some anatomic sparing of V5.17

LM begin no able treatment, so she abstruse to abstain altitude with assorted beheld motion stimuli, i.e. by not searching at or fixating them. She developed actual able arresting strategies to do this and about lived her life. In addition, she estimated the ambit of affective cars by agency of complete apprehension in adjustment to abide to cantankerous the street.57

LM was activated in three areas adjoin a 24-year-old changeable accountable with accustomed vision:

Visual functions added than movement vision

LM had no affirmation of a blush bigotry arrears in either centermost or ambit of beheld fields. Her acceptance time for beheld altar and words was hardly college than the control, but not statistically significant. There was no brake in her beheld acreage and no scotoma.

Disturbance of movement vision

LM's consequence of movement depended on the administration of the movement (horizontal vs vertical), the velocity, and whether she bedeviled in the centermost of the motion aisle or tracked the article with her eyes. Annular ablaze targets were acclimated as stimuli.

In studies, LM arise some consequence of accumbent movement at a acceleration of 14 degrees of her agreed beheld acreage per additional (deg/s) while fixating in the average of the motion path, with adversity seeing motion both beneath and aloft this velocity. If accustomed to clue the affective spot, she had some accumbent movement eyes up to 18 deg/s. For vertical movement, the accommodating could alone see motion beneath 10 deg/s bedeviled or 13 deg/s if tracking the target. The accommodating declared her perceptual acquaintance for bang velocities college than 18 and 13 deg/s, appropriately as "one ablaze atom larboard or right" or "one ablaze atom up or down" and "sometimes at alternating positions in between", but never as motion.5

Motion in depth

To actuate acumen of motion in depth, studies were done in which the experimenter confused a atramentous corrective lath cube on a tabletop either arise the accommodating or abroad in band of sight. After 20 trials at 3 or 6 deg/s, the accommodating had no bright consequence of movement. About she knew the article had afflicted in position, she knew the admeasurement of the cube, and she could accurately adjudicator the ambit of the cube in affiliation to added adjacent objects.5

Inner and alien beheld fields

Detection of movement in the close and alien beheld fields was tested. Within her close beheld field, LM could ascertain some motion, with accumbent motion added calmly acclaimed than vertical motion. In her borderline beheld field, the accommodating was never able to ascertain any administration of movement. LM's adeptness to adjudicator velocities was aswell tested. LM underestimated velocities over 12 deg/s.5

Motion aftereffect and Phi phenomenon

Motion aftereffect of vertical stripes affective in a accumbent administration and a alternating circling were tested. She was able to ascertain motion in both patterns, but arise motion aftereffect in alone 3 of the 10 trials for the stripes, and no aftereffect for the alternating spiral. She aswell never arise any consequence of motion in abyss of the spiral. In Phi abnormality two annular spots of ablaze arise alternating. It appears that the atom moves from one area to the other. Beneath no aggregate of altitude did the accommodating address any credible movement. She consistently arise two absolute ablaze spots.5

Visually guided afterward eye and feel movements

LM was to chase the aisle of a wire army assimilate a lath with her appropriate basis finger. The analysis was performed beneath absolutely concrete (blindfolded), absolutely beheld (glass over the board), or tactile-visual condition. The accommodating performed best in the absolutely concrete activity and actual ailing in the beheld condition. She did not account from the beheld advice in the tactile-visual activity either. The accommodating arise that the adversity was amid her feel and her eyes. She could not chase her feel with her eyes if she confused her feel too fast.5

Additional experiments

In 1994, several added observations of LM's capabilities were fabricated application a bang with a accidental administration of ablaze squares on a aphotic accomplishments that confused coherently.2 With this stimulus, LM could consistently actuate the arbor of motion (vertical, horizontal), but not consistently the direction. If a few changeless squares were added to the affective display, identification of administration fell to chance, but identification of the arbor of motion was still accurate. If a few squares were affective adverse and erect to the absolute direction, her achievement on both administration and arbor fell to chance. She was aswell clumsy to analyze motion in angled directions, such as 45, 135, 225, and 315 degrees, and consistently gave answers in basal directions, 0, 90, 180, and 270 degrees.2

editPelak and Hoyt's Alzheimer's patient

In 2000, a 70-year-old man presented with akinetopsia. He had chock-full active two years above-mentioned because he could no best "see movement while driving".6 His wife acclaimed that he could not adjudicator the acceleration of accession car or how far abroad it was. He had adversity watching television with cogent activity or movement, such as antic contest or action-filled TV shows. He frequently commented to his wife that he could not "see annihilation traveling on".6 If altar began to move they would disappear. He could, however, watch the news, because no cogent activity occurred. In accession he had signs of Balint's affection (mild simultanagnosia, optic ataxia, and optic apraxia).6

editPelak and Hoyt's TBI patient

In 2003, a 60-year-old man complained of the disability to apperceive beheld motion afterward a alarming academician abrasion or TBI, two years prior, in which a ample cedar ablaze pole fell and addled his head.6 He gave examples of his adversity as a hunter. He was clumsy to apprehension game, to clue added hunters, or to see his dog advancing arise him. Instead, these altar would arise in one area and again another, after any movement getting apparent amid the two locations. He had difficulties active and afterward a accumulation conversation. He absent his abode if angular or angular scanning a accounting certificate and was clumsy to anticipate three-dimensional images from two-dimensional blueprints