Visual System Structure and Processing (6A) Practice Test

A patient has difficulty perceiving the direction of moving stimuli but can accurately report the color and shape of stationary objects. In a clinic test, they fail to determine whether dots move left or right at high coherence. Which explanation best accounts for this selective impairment?

A clinician presents a patient with a vertical line while recording neural responses. The patient shows normal detection when the line is tilted slightly, but detection drops sharply when the line is perfectly vertical. The clinician suspects the patient is relying on a limited subset of orientation-sensitive neurons due to cortical reorganization after injury. Based on this scenario, which conclusion is most consistent with the principle of feature detection in visual processing?