Ch 14 - Parietal Lobes and Networks

Posterior Parietal Cortex

A neocortical region posterior to the central fissure and anterior to the occipital cortex; represents our somatosensory regions; receives and integrates information from vision, touch, and hearing with our body senses; and can initiate and direct movements in response to information from any of our senses

Saccade

A series of involuntary, abrupt, and rapid small movements or jerks of both eyes

Sensorimotor Transformation

Neural calculations that integrate the movements of different body parts (eyes, body, arm, etc.) with the sensory feedback of what movements are actually being made and the plans to make the movements. Sensorimotor transformation depends on both movement-related and sensory-related signals produced by cells in the posterior parietal cortex

Acalculia

Inability to perform mathematical operations

Stereognosis

Tactile perception; recognition of objects through the sense of touch

Afferent Paresis

Loss of kinesthetic feedback that results from lesions to the postcentral gyrus (areas 3-1-2) and produces clumsy movements

Astereognosis

Inability to recognize the nature of an object by touch

Stimultaneous Extinction

The somatoperceptual disorder most commonly associated with damage to the secondary somatic cortex (areas PE and PF), especially in the right parietal lobe; two stimuli would be reported if applied singly, but only one would be reported if both were applied together; the second stage of recovery from contralateral neglect characterized by response to stimuli on the neglected side as if there were a simultaneous stimulation on the contralateral side

Numb Touch

A tactile analogue of blindsight, in which individuals have lost tactile perception but are able to locate objects through touch. Also called blind touch

Asomatognosia

Loss of knowledge or sensory awareness of one’s own body and bodily condition; may be on one or both sides of the body; most commonly results from damage to the right parietal lobe

Anosognosia

Loss of ability to recognize or to acknowledge an illness or a bodily defect; usually associated with right parietal lesions

Anosodiaphoria

Indifference to illness

Autopagnosia

Inability to localize and name the parts of one’s own body — for example, finger agnosia

Asymbolia for Pain

Inability to understand the meaning of or react to pain

Finger Agnosia

An inability to distinguish fingers; most common form of autopagnosia

Contralateral Neglect

Neglect of part of the body or space contralateral to a lesion. Also called neglect

Allesthesia

A stage of recovery from contralateral neglect characterized by a person’s beginning to respond to stimuli on the neglected side as if the stimuli were on the unlesioned side

Agraphia

Decline in or loss of the ability to write

Apraxia

The inability, in the absence of paralysis or other motor or sensory impairment, to make or copy voluntary movements, especially an inability to make proper use of an object

Ideomotor Apraxia

An inability to use and understand nonverbal communication such as gesture and pantomime or to copy movement sequences

Constructional Apraxia

A visuomotor disorder in which spatial organization is disturbed

Disengagement

The process by which attention is shifted from one stimulus to another