Cognitive Assessment Flashcards
(17 cards)
Visual neglect
Visual neglect-Neglect of personal and extrapersonal space is usually caused by lesions to the right hemisphere—usually the inferior parietal or prefrontal regions. Deficits can be uncovered by simultaneous bilateral sensory or visual stimulation, or having the patient bisect lines of variable length. Letter and star cancellation tasks are similar, more formal tasks.
Visual agnosia
Visual object agnosias cause a failure of object recognition despite adequate perception. Those with apperceptive visual agnosia have normal basic visual functions, but fail on more complex tasks involving object identification and naming.
Constructional apraxia
Constructional apraxia is inability to construct elements to a meaningful whole. E.g. inability to draw or copy simple diagrams or figures. This is typically caused by a lesion in the right cerebral hemisphere.
Alexia without agraphia (pure alexia)
patients retain the ability to write, but are unable to read (even words that they have just written) and
often have right homonymous hemianopia.
This disorder results from the loss of visual input to the language area [usually the dominant (left) angular gyrus] without involvement of the language area or output from the language area to the motor cortex.
The ability to process visual input into language (i. e., reading) is lost in these patients.
The pathways involved in this syndrome are believed to be localized to the inferior portion of the splenium of the corpus callosum on the side of the dominant (usually left) cerebral hemis- phere.
This is asosicated with posterior cerebral artery damage.
Prosopognosia
Prosopagnosia (face blindness) is a disorder of face perception where the ability to recognize faces is impaired
Simultanagnosia
Simultanagnosia is a rare neurological disorder characterized by the inability of an individual to perceive more than a single object at a time;
where does Middle cerebral artery supply
DLPFC consists of the lateral portions of Brodmann areas 9 – 12, of areas 45, 46, and the superior part of area 47. These regions mainly receive their blood supply from the middle cerebral artery
Argyll Robertson Pupil
Argyll Robertson Pupil (ARP): The pupils are bilaterally small and reduce in size when the patient focuses on a near object (i.e. Accommodation Reflexes Present – ARP again!) but do not constrict when exposed to bright light (i.e. pupillary reflexes absent).
They are seen in patients with neurosyphilis (hence the name “Prostitute’s Pupil”) and diabetic neuropathy.
Argyll Robertson Pupil
Argyll Robertson Pupil (ARP): The pupils are bilaterally small and reduce in size when the patient focuses on a near object (i.e. Accommodation Reflexes Present – ARP again!) but do not constrict when exposed to bright light (i.e. pupillary reflexes absent).
They are seen in patients with neurosyphilis (hence the name “Prostitute’s Pupil”) and diabetic neuropathy.
Ideomotor apraxia
disorder of goal-directed movement.
Patient knows what to do but not how to do it. There is an inability to mimic a learned motor task or behavior, such as combing one’s hair.
results from damage to the dominant parietal lobe. Abnormalities include (i) abnormal amplitude of motor movements (ii) body-part-as-object substitution, e.g. the patient uses his own finger to represent a toothbrush when asked to brush his teeth; (iii) abnormal orientation of body parts when attempting to perform an action.
Orobuccal apraxia
Orobuccal apraxia is closely associated with lesions of the left inferior frontal lobe
and the insula, and commonly accompanies the aphasia caused by lesions of
Broca’s area
Progressive, isolated limb apraxia
is virtually diagnostic of corticobasal
degeneration.
Oculomotor apraxia:
Horizontal eye movement diffuclties seen in children. It is a
rare degenerative disorder of the nervous system that usually affects the ability of
the patients to quickly move their eyes from side to side and often have to turn
their head (head jerking) and not just their eyes to track an objec
Oculomotor apraxia:
Horizontal eye movement diffuclties seen in children. It is a
rare degenerative disorder of the nervous system that usually affects the ability of
the patients to quickly move their eyes from side to side and often have to turn
their head (head jerking) and not just their eyes to track an objec
Limb-kinetic apraxia
Loss of hand and finger dexterity resulting from inability to connect or isolate individual movements. Affects use of tools, gestures, especially distal fingers movements. Can be either ideomotor or ideational type
Dominant Fronto- parietal or
primary motor cortex
Question 41.
A 50-year-old man on a neurology ward has non-dominant parietal lobe dysfunction. Identify the test that he is least likely to be able to do?
Copying intersecting pentagons Correctly stating current location Reading a sentence Serial subtraction of 7s from 100 Writing a sentence
The cognitive process tested by asking the patient to copy intersecting pentagons is constructional praxis, which is a feature of non-dominant parietal lobe lesions. The effects of lesion involving non-dominant parietal lobe include visuospatial dysfunction, topographical memory loss, and constructional / dressing apraxia. These disorders could be seen in lesions of either hemisphere but observed more frequently and are of greater severity with lesions of the non-dominant parietal lobe.
The behavioural despair test used in animals:
also called the Porsolt test or forced swimming test)
used to measure the effect of antidepressant drugs on the behaviour of laboratory animals (typically rats or mice).
Animals are subjected to two trials during which they are forced to swim in an acrylic glass cylinder filled with water.
The first trial lasts 15 minutes. Then, after 24-hours, a second trial is performed that lasts 5 minutes. The time that the test animal spends without moving in the second trial is measured. This immobility time is decreased by antidepressants.
