Citations

Studies of the effect of therapy on the course of recovery from aphasia yield inconsistent results and permit no generalization to the population of aphasic patients. Future investigations of the efficacy of therapy should specify the nature of the language disorders treated, the limits of the period of spontaneous recovery, objective measurement of relevant behavioral changes, and the nature, intensity, and quality of therapy provided. In subject selection, age, educational and social status, intelligence, health, social milieu, etiology, site and extent of lesion, time lapse since onset, type of aphasia, and nonlanguage behavior characteristics should be controlled if interpretable results are to be obtained.

To identify behaviors which might distinguish developmental apraxia of speech from “functional” articulation disorders, 30 children with moderate to severe defective articulation but with normal intelligence, hearing, and language abilities and with no apparent organic pathologic condition and a group of matched control subjects were given a battery of speech and nonspeech tests. Pediatric neurologic examinations were completed for the subjects with defective articulation. Speech data were analyzed according to type of articulation error and by a method of distinctive-feature categorization. Highly significant differences were found between control and defective articulation subjects. A rationale was established for division of the defective articulation group on the basis of their performance on isolated volitional oral movement tasks. Combinations of variables that emerged as statistically significant differentiating predictors between these two subgroups of subjects with defective articulation were neurologic ratings, two- and three-feature errors, distortions, prolongations and repetitions, additions, one-place errors, and omissions. These behavioral differences support the conclusion that an identifiable developmental apraxia of speech exists in some children with defective articulation.

In a test of auditory perception of phonemes, 10 patients with apraxia of speech were compared with 10 matched normal control subjects on a task of pointing to pictures designated by sequences of auditory word stimuli. The test items were 190 sequences of two and three words with minimal variation of initial consonant, final consonant, medial vowel, or multiple phonemes. The apraxic patients made significantly more perceptual errors as a group, but varied considerably in their level of performance. The achievement of some patients was within the range established by the control subjects; that of others was unequivocally inferior. The major deficit in the apraxic group appeared to be impairment of ability to retain the second- and third-syllable consonant elements in three-word sequences. Apraxia of speech can occur in relatively pure form in the absence of auditory perceptual impairment. It can also occur in conjunction with reduced auditory retention span, which impairs the perception of sequences of words which are minimally varied phonemically.

This study explored the effects of various tasks, designed to alter the degree of “attention to stimuli” on the variability of the EEG activity which gives rise to the average acoustically evoked response. Evoked responses to 50 dB SL clicks were recorded from the vertex of eight male subjects under four conditions (1) quiet, (2) .counting, (3) discriminating, and (4) reading. Results showed the quiet condition to yield the greatest variability while reading exhibited the least.

Less than half of a series of 168 patients with multiple sclerosis presented significant speech deviations. The most frequent speech deviations observed were impaired loudness control and harshness; less frequently occurring deviations were defective articulation, restricted use of vocal variations for emphasis, poor pitch control, hypernasality, inappropriate pitch level, and breathiness. “Scanning speech” was not a prominent characteristic. Speech deviations were not solely attributable to cerebellar involvement. Their incidence was positively related to severity of neurologic involvement, becoming more prominent as additional motor systems were implicated.