Aphasia, Agnosia, Apraxia, and Amnesia | The Massachusetts General Hospital Handbook of Neurology

Authors: Flaherty, Alice W.; Rost, Natalia S.

Title: Massachusetts General Hospital Handbook of Neurology, The, 2nd Edition

> Table of Contents > Adult Neurology > Aphasia, Agnosia, Apraxia, and Amnesia

Aphasia, Agnosia, Apraxia, and Amnesia

A. Aphasia

Language disorder versus the motor disorder of dysarthria.

Table 2. Major aphasia categories.

Type of Aphasia	Speech Fluent?	Compre-hends?	Repeats Phrases?	Lesion Location
Global	No	No	No	Does not localize
Expressive (Broca's)	No	Yes	No	Inf. frontal gyrus
Receptive (Wernicke's)	Yes	No	No	Sup. temporal gyrus
Transcortical motor	No	Yes	Yes	Premotor cortex
Transcortical sensory	Yes	No	Yes	Occipitotemporal cx.
Conductive	Yes	Yes	No	Subcortical MCA territ.
Amnestic (anomia)	Yes	Yes	Yes	Alzheimer's, etc.

1. Three questions: Is the pt.'s speech fluent? Does pt. comprehend speech? Can pt. repeat it? See endpapers at back of book for picture naming and reading samples.
2. Jargon-based aphasia of the physician (JBAP): Onset between the third year of medical school and internship. Speech fluent but incomprehensible in severe cases. JBAP lowers pt compliance (see p. 105). Pathognomonic signs include saying lower extremity instead of leg to a pt., or saying micturition to anyone at all.

B. Evolution of aphasia

Expressive or receptive aphasia from strokes commonly starts as global aphasia acutely; only later becomes clearly productive or receptive aphasia. The amnestic aphasia of Alzheimer's dz may evolve into a full-blown receptive aphasia.

C. Alexia, agraphia, and acalculia

Respectively, inability to read, write, or do arithmetic. Usually from lesions of the left angular gyrus. For alexia without agraphia, see Eyes and Vision, p. 44.

D. Amnesia

Poor memory storage (anterograde amnesia) or recall (retrograde amnesia). Often a hippocampal or paramedian thalamic lesion.

E. Agnosia

Impairment of recognition in a single modality, as opposed to amnesia, in which impairment includes all modalities.

1. Anosognosia: Unawareness of neurological deficit. Usually from right parietotemporal lesion.
2. Neglect: Disregard of stimuli arising from one side of the body, usually the left, from right parietal lesion.
3. Object agnosia: Usually from bilateral posterior temporal lobe lesion.
4. Visual agnosias: see p. 45.

P.16

F. Apraxia

Inability to do a task for cognitive rather than motor reasons.

1. Ideomotor apraxia: Disordered complex movement sequencing, e.g., perseveration or distortion. Often L premotor or parietal lesion.
2. Constructional apraxia: Disorder of spatial design, drawing. Usually R parietal lesion.