PSYC55H3 Lecture Notes - Disabilities Affecting Intellectual Abilities, Single-Photon Emission Computed Tomography, Wechsler Adult Intelligence Scale
Document Summary
Ventral occipital lesions impair object recognition but not object-directed grasping: an fmri study. There are two primary pathways in the nervous system which process information about object perception and object location. These have been identified by ungerleider and mishkin as ventral and dorsal pathways respectively. One of the most famous cases of damage in ventral stream pathway was observed in patient d. f which resulted in visual form agnosia. Structural fmri revealed d. f suffered damage particularly in ventrolateral regions of occipital lobe with dorsal and primary visual cortex intact. In this fmri study patient d. f along with healthy subjects participated in two separate experiments which assessed their performance on tasks designed to measure ventral or dorsal function (thomas et al 2003). Experiment 1 was designed to assess ventral stream pathway by the use of two dimensional objects of varying color, line drawings or grayscale images. For evaluating dorsal stream pathway simple three dimensional objects were used in a grasping task.