Cortical Lesions

Question 1

Cortical Disorders Major Category

Answer 1

Diffuse

Focal

Question 2

Cortical Disorders Diffuse

Answer 2

e.g. degenerative (Alzheimer’s Disease), metabolic (hypoxia)

Question 3

Cortical Disorders Focal

Answer 3

. vascular (stroke), traumatic (contusion), neoplastic (tumor)

Question 4

Frontal Lobe Functions

Answer 4

Voluntary movement
Language production (left)
Motor prosody (right)
Comportment
Executive function
Motivation

Question 5

Temporal Lobe Functions

Answer 5

Audition
Language comprehension (left)
Sensory prosody (right)
Memory 
Emotion

Question 6

Parietal Lobe Functions

Answer 6

Tactile sensation
Visuospatial function (right)
Attention (right)
Reading (left)
Writing (left)
Calculation (left)

Question 7

Occipital Lobe Functions

Answer 7

Vision
Visual perception
Visual recognition

Question 8

Frontal lobe lesions produce deficits in motor function (upper motor neuron involvement), language, prosody, and neuropsychiatric disorders (frontal lobe syndromes)

Answer 8

In general, neurobehavioral effects are more florid and persistent with bilateral lesions

Question 9

Frontal Lobe Syndromes

Answer 9

Disinhibition – orbitofrontal cortices
Executive dysfunction – dorsolateral prefrontal cortices
Apathy – medial frontal cortices

Question 10

Considerable evidence implicates damage to the frontal lobes as having an impact on the propensity for: ________

Answer 10

violence

Question 11

This is a disturbance of comportment, the capacity to maintain an appropriate behavioral repertoire in the face of social situations where limbic drives are influential and impulse control is critical

Patients may show irritability, loss of empathy, impulsivity (pathological gambling, excessive spending, etc.), hypersexuality, hyperphagia, and violence

Answer 11

Disinhibition- loss of social grace

orbitofrontal cortices

Question 12

A term that implies frontal lobe damage
One feature of frontal lobe damage is perseveration, an impairment of the capacity to shift responses appropriately
The alternating sequences test can demonstrate perseveration, as in this example from an AD patient

Answer 12

Executive Dysfunction- Plan/ coordinate

dorsolateral prefrontal cortices

Question 13

At the cortical level, motivation is mainly subserved by the medial frontal cortices, including the anterior cingulate gyrus
Clinical syndromes include apathy, abulia, and most severely, akinetic mutism

Answer 13

Apathy- you just quit

medial frontal cortices

*Cingulate gyrus may be the center of will

Question 14

Lesions of the temporal lobe have minor effects on audition, but often major effects on ___________

Answer 14

language, prosody, memory, and emotion

In terms of the emotions, the effects of temporal lobe lesions result from irritative lesions of the cortex that cause epilepsy

Question 15

____________ is usually caused by right hemisphere lesions, with inattention to the left side of space
The lower drawing was done by a man with a recent right parietal infarct

Answer 15

Hemineglect

Question 16

Visual Agnosia

Answer 16

Visual agnosia is a failure to recognize objects that are adequately seen
Recognition requires the dorsal and ventral visual association cortices

Examples: object agnosia (left occipitotemporal), prosopagnosia (right occipitotemporal), achromatopsia (bilateral occipitotemporal), and simultanagnosia (bilateral occipitoparietal)

Question 17

In terms of the emotions, the effects of temporal lobe lesions from irritative lesions of the cortex that cause ___________

Answer 17

epilepsy

Irritative lesion= hyperactive cortex

Question 18

The right hemisphere has the capacity to attend to both sides of space, whereas the left can only attend to the contralateral space

Right vs Left Lesion?

Answer 18

Thus a right parietal lesion will only permit surveillance of the right hemispace

Left hemineglect is more severe and lasting than right hemineglect

Question 19

The aphasia resulting from damage to Wernicke’s area

Fluent, paraphasic speech with impaired auditory comprehension, repetition, and naming

Answer 19

Wernicke’s Aphasia- Temporal

Question 20

Cannot hear inflections of speech

Analogous to Wernicke’s aphasia, sensory aprosody is the inability to comprehend the prosody of others

Answer 20

Sensory Aprosody

Question 21

Limbic lesions often disturb ____________-

Papez circuit: basic emotions

Answer 21

emotional function

Question 22

Common form of epilepsy, related to focal cortical lesions that produce complex partial seizures
Many behavioral phenomena can be associated with these seizures

Answer 22

Temporal Lobe Epilepsy (TLE)

Question 23

Considerable evidence exists to show that __________ produces lasting changes in behavior because of ongoing subclinical and clinical electrical activity that rewires temporolimbic circuitry

Answer 23

TLE

Question 24

Hemineglect is usually caused by

Answer 24

RIGHT hemisphere lesions- prototype parietal lobe syndrome

Bad attention to left side of space

Question 25

Thus a right parietal lesion will only permit surveillance of the right hemispace
Left hemineglect is ________________–

Answer 25

more severe and lasting than right hemineglect

Question 26

A right parietal lesion will _______________

Left hemineglect is more severe and lasting than right hemineglect

Answer 26

only permit surveillance of the right hemispace

Question 27

Occipital lesions produce visual field deficits: most common are ____________

Answer 27

hemianopia and quadrantanopia