Super Memory Formula
APHEMIA
Aphemia was the term originally used by Broca to describe all language disturbances, but he later accepted the term aphasia promoted by Trousseau (1864). Bastian (1887) used aphemia to denote a specific syndrome described here; others have termed the same language abnormality pure motor aphasia, cortical anarthria, or apraxia of speech.
The patient presents acutely with mutism but is able to communicate using written language. When verbalization returns, the output is hypophonic, slow, and poorly articulated so as to be almost incomprehensible. Comprehension of spoken language is intact. Although both repetition and naming are severely disturbed because they demand vocalization, patients can comprehend written language and are able to write without difficulty. Primary laryngeal pathology should be ruled out.
Neurological examination reveals a transient right hemiplegia or hemiparesis without other neurological signs except for an often associated buccofacial apraxia. Patients have difficulty performing on command acts such as whistling, sucking, blowing, and winking. In contrast, they have no trouble performing limb activities such as imitating the use of a comb or a toothbrush, waving goodbye, and saluting.
In aphemia, the communication disturbance involves verbal output and is a speech problem rather than an impairment of language. There is often an overlap, however, between aphemia and the anterior aphasia syndromes. An aphemia-like state appears in some patients who have recovered from Broca's aphasia. Some investigators have even considered aphemia to be a minor subtype of Broca's aphasia, also called little Broca's aphasia.
However, aphemia differs from true Broca's aphasia because of the absence of agrammatism in the spoken and written output. Most often, aphemia improves to useful language output, but a dysprosodic speech quality remains, producing a so-called foreign accent syndrome, a disorder of rhythm, inflection, and articulation, suggesting that the patient is not a native speaker of the language. The pathology is located in or immediately inferior to Broca's area in the dominant hemisphere (see Fig. 6,-5 ).[gi
TABL |
E 6-5 -- CLINICO-ANATOMICAL CORRELATIONS OF SPEECH AND LANGUAGE DISORDERS | |||
Anatomical Site of Damage |
Speech or Language Syndrome |
Other Neurological and Medical Findings |
Common Etiologies |
Comments |
(L) Posterior inferior frontal lobe |
Broca's aphasia |
Brachiofacial weakness |
Stroke, trauma, tumor, infection |
Initial (L) conjugate gaze deviation |
(L) Posterior superior temporal gyrus |
Wernicke's aphasia |
Visual field deficit |
Stroke, temporal lobe abscess | |
(L) Posterior sylvian region |
Conduction aphasia |
Cortical sensory deficit pseudothalamic pain |
Stroke |
Associated ideomotor apraxia |
(L) Sylvian region |
Global aphasia |
Hemianopia, hemiplegia |
Stroke, tumor, trauma, infection | |
(L) Dorsolateral frontal cortex |
Transcortical motor aphasia |
Buccofacial apraxia, hemiparesis is occasional |
Anterior border zone vascular infarction | |
(L) Temporoparieto-occipital junction |
Transcortical sensory aphasia |
Cortical sensory deficit Visual field deficit |
Posterior border zone vascular infarction Degenerative disease |
Echolalia is common |
(L) Hemisphere, vascular border zone areas |
Mixed transcortical aphasia |
Variable motor, sensory, and visual field deficits |
Border zone infarctions, anoxia, carbon monoxide poisoning |
Echolalia very common |
(L) Thalamus, striatum white matter |
Subcortical aphasia |
Hemiplegia/sensory loss |
Stroke, ischemic and hemorrhagic |
No visual field or cortical sensory loss |
Unilateral or bilateral corticobulbar tracts |
Spastic dysarthria |
Unilateral or bilateral hyperreflexia or spasticity |
Stroke, demyelinating and degenerative disease |
Cerebellum |
Ataxic dysarthria |
Dysmetria, nystagmus ataxia |
Stroke, degenerative, toxic disorder; tumor | |
Lower motor neuron brain stem or peripheral nerves |
Flaccid dysarthria |
Atrophy, fasciculation, decreased gag |
Motor neuron disease, stroke, carcinomatous meningitis |
Risk of aspiration pneumonia |
Hypokinetic/hyperkinetic dysarthria |
Parkinsonism, dystonia, chorea |
Degenerative disease, Parkinson's disease, Huntington's disease, stroke | ||
Vocal cords or their innervation |
Dysphonia |
Fatiguability, ptosis |
Laryngitis, vocal cord paralysis, myasthenia |
May be a sign of laryngeal carcinoma |
Pure word deafness is a rare prelanguage syndrome in which only reception of spoken language is involved. Individuals with pure word deafness do not understand spoken language and cannot repeat. However, they are able to hear and identify adequately nonverbal sounds such as a whistle, a telephone ring, and a dog bark. Their reading is intact, and they often carry with them a writing tablet for others to use. y
There are two known loci of pathology. Some patients have a single lesion deep in the dominant superior temporal region affecting the primary auditory cortex or the pathways to it from the medial geniculate nucleus. More commonly, there is bilateral pathology involving the mid-portion of the superior temporal gyrus of both hemispheres. Wernicke's area (left auditory association cortex) is not involved.
Some cases of pure word deafness have associated paraphasic output and mild written language comprehension deficits. These cases should be classified as Wernicke's aphasias with predominant word deafness and relatively less word blindness (reading comprehension).
Pure word deafness is not a disturbance of language ability. Delivery of the auditory signal to the area mediating language interpretation is defective, which is a sensory transmission problem rather than a language disturbance. Pure word deafness resembles deafness more than aphasia. It has also been called auditory verbal agnosia.y Although pure word deafness is rare in isolation, it may be associated with posterior aphasic disorders.
Delirium with fluctuating consciousness and disturbed thought content is associated with variable language difficulties with or without structural brain pathology. Patients often have impaired attention and do poorly on tasks such as digit span and mental control. Language disturbances can be the presenting feature of delirium, particularly in patients with decreased attention and concentration. Associated features may include agitation, hallucinations, confusion, and myoclonus.
Psychiatric disorders can occasionally mimic classic language syndromes. Schizophrenics often present with verbal output described as word salad, containing bizarre words and sentences. Written output parallels the content of verbal output. These patients have no other language disturbances and are usually readily distinguished from Wernicke's or other posterior aphasias. Manic patients often present with logorrheic output, pressured speech, and grandiose content; but no other language disturbances are
encountered that distinguish them from other classic aphasia syndromes. RIGHT HEMISPHERE DISORDERS
Right hemisphere disorders can affect language function, most commonly in left-handed individuals. Rarely, right-handed patients become aphasic after strokes in the right hemisphere, a phenomenon called crossed aphasia in dextrals. Even in right-handed people with typical left hemisphere dominance for language, subtle alterations in language function occur after right hemisphere damage. The right hemisphere has a dominant role for expressing emotion including emotional prosodic aspects of communication.^ Amelodia (also called affective motor aprosodia) is a disturbance characterized by loss of melody, prosody, or emotional intonation in verbal output.y There is a flat monotonous verbal output, inability to produce a melody when singing (expressive amusia), decreased facial expression, and sparse use of gestures. The result is a seemingly emotionless response, which is easily misinterpreted as depression. The neuropathology involves the right frontal opercular area and its connections, which is the right hemisphere equivalent of Broca's area. In addition, receptive amusia and other disorders of music appreciation are related disturbances predominantly associated with right hemisphere lesions.
Tables 6-5 and 6-6 summarize clinico-anatomical correlations
Etiological Category |
Selected Specific Etiologies |
Chapter |
STRUCTURAL DISORDERS | ||
Developmental |
Arnold-Chiari malformat ons |
28 |
HEREDITARY AND DEGENERATIVE DISORDERS | ||
Storage diseases: Lipidoses, glycogen disorders and leukoencephalopathies |
Adrenoleueodystrophy, Krabbe's disease, metachromatic leucodystrophy |
30 |
The degenerative dementias |
Alzheimer's disease, fronto-temporal degeneration, Parkinson's disease, Huntington's disease |
33 |
Movement disorders |
Hallervorden-Spatz disease, Wilson's disease, progressive supranuelear palsy, Parkinson's disease, multiple system atrophy, Huntington's disease |
34 |
Ataxias |
Friedreich's ataxia, abetalipoproteinemia |
35 |
Degenerative motor, sensory, and autonomic disorders |
Amyotrophic lateral sclerosis |
36 |
Inherited muscle, neuromuscular, and neuronal disorders |
Myopathies |
37 |
ACQUIRED METABOLIC AND NUTRITIONAL DISORDERS | ||
Endogenous metabolic disorders |
38 | |
Exogenous aequired metabolic disorders of the nervous system: Toxins and illicit drugs |
39 | |
Nutritional deficiencies and syndromes associated with alcoholism |
Alcoholic cerebellar degeneration Vitamin E deficiency |
40 |
INFECTIOUS DISORDERS | ||
Viral infections |
Herpetic encephalitis |
41 |
Nonviral infections |
Toxoplasmosis or bacterial abscess of the temporal lobe |
42 |
Transmissible spongiform encephalopathies HIV and AIDS
Was this article helpful?
I leave absolutely nothing out! Everything that I learned about Alzheimer’s I share with you. This is the most comprehensive report on Alzheimer’s you will ever read. No stone is left unturned in this comprehensive report.
Post a comment