Blood pressure reactivity to active and passive behavioral conditions in hypertensives and normotensives

Blood pressure reactivity and passive behavioral tasks was studied in patients with mild essential hypertension and normotensive controls. The passive condition included 10 presentations of a 6 sec, 78 dB, 1000 Hz tone without any response requirements. In the active condition subjects were given an additional 10 tone presentations and asked to press a push-button at tone termination. The absolute and percent increase in systolic blood pressure from rest was greater in hypertensives than normotensives in response to the active condition but similar to the passive condition. It is concluded that patients with hypertension compared to normotensive controls show exaggerated blood pressure reactivity to tasks involving active but not passive coping efforts. Since the tasks used to induce active and passive coping in the present study were identical apart from coping requirements, the notion that the activity dimension in and of itself modulates reactivity differences between patients and controls is supported.     

Hemispheric alpha asymmetries and behavioral responses of aphasic and normal subjects for the recall and recognition of active, passive, and negative sentences

The hemispheric alpha asymmetries of a group of normal males, a group of normal females, and a group of aphasic patients (fluent and dysfluent) were examined with electroencephalographic (EEG) techniques under memory conditions of recall and recognition of active, passive, and negative sentences. Aphasic patients, regardless of classification, showed right hemispheric alpha suppression across memory conditions and sentence types. Both normal groups were found to have greater left hemispheric alpha suppression for the recall memory condition and greater right hemispheric alpha suppression for the recognition memory condition (males significantly more than females). The aphasic subjects performed better on recognition tasks compared to recalled tasks and active sentences compared to transformed sentences. Results are discussed as providing evidence of the aphasic subjects' greater dependency on information processing resources of the right hemisphere in the recovery of language function. The findings are also discussed as providing support for a multiple-resources model of information processing.     

Verbal self-correction behaviors of fluent and nonfluent aphasic subjects

This investigation examined the use of six explicitly defined verbal self-correction behaviors by fluent and nonfluent aphasic subjects of high and low verbal ability, and by subjects further classified into six groups according to type of aphasia (Broca's, Anomic, Wernicke's etc.). Aphasic groups, on the average, generated some type of verbal self-correction effort on more than half of their initially erroneous responses, and the proportions of these efforts did not differ between aphasic patient groups. Significant differences in self-correction success were found, however, between groups classified according to fluency and severity, as well as among the six groups based on type of aphasia. In the former case, distinctions in self-correction skill favored high-verbal-ability groups regardless of fluency classification. In the latter instance, the subgroups typically formed by less severely impaired patients (Anomic and Broca's) had significantly higher proportions of successful self-correction behaviors than those comprised of individuals with more severe involvement (Wernicke's and Broca's plus severely limiting apraxia of speech). Between-group differences for specific types of self-correction behaviors occurred rarely, but those which were found could be related to characteristics of the particular aphasic groups under consideration. Verbal self-correction behavior is discussed as a behavioral reaction to an erroneous response or dissatisfaction with the quality of an intended response. These behaviors are viewed as indicators of the intactness of an aphasic individual's self-monitoring system, and of his tolerance for responses that are qualitatively limited by his verbal deficits.     

Effects of imposed delay of response and item complexity on auditory comprehension by aphasics

Ten aphasic and five control subjects were administered an auditory comprehension task similar to Levels I-IV of the Revised Token Test under conditions of 0, 5, 10, and 20 sec of imposed response delay. Responses were evaluated in terms of performance accuracy and response time. Aphasic subjects' response accuracy was significantly effected by an interaction between the length of delay imposed and the complexity of the stimulus. The aphasic group also demonstrated a significant main effect for item complexity. Control subjects' accuracy was not influenced by the treatment conditions. Latency measures indicated the aphasic subjects were slower to respond across all treatment conditions. Both groups' latency scores were significantly effected by item complexity. A comparison of mean latencies by condition did, however, suggest different patterns of response for the two groups. Results are discussed in terms of theoretical and clinical implications for the auditory comprehension deficits of aphasia.     

Auditory event-related potential probes and behavioral measures of aphasia

This study examined the relationship between an auditory event-related potential probe technique measure of differential hemispheric processing and traditional tests of aphasia in aphasic patients. Subjects were 10 aphasic and 10 normal adult males. The results of the electrophysiological measures indicated that the aphasic subjects responded differently from the normal group particularly when the task required processing of verbal information. During the verbal task the aphasic group showed higher amplitude right hemisphere responses as compared to left. The normal group showed little hemispheric task related asymmetries. The pattern of electrical asymmetry in the aphasic group seems to be an indicator of severity as measured by traditional aphasia examinations.     

Assessment of the relationship of cerebral hemisphere arousal asymmetry to perceptual asymmetry.

This study examined the hypothesis that characteristic individual differences in cerebral hemisphere arousal asymmetry are related to individual differences in perceptual asymmetry observed in verbally based visual half-field tasks. The study used electrophysiological measures of arousal asymmetry rather than behaviorally derived measures (Levy, Heller, Banich, & Burton, 1983). Measures of alpha asymmetry were obtained from 20 right-handed males during a baseline relaxation condition and during a visual half-field version of the lexical decision task. Reaction time measures of perceptual asymmetry were obtained during this task. The results indicated that a basal arousal asymmetry measured at the temporal recording location during the baseline condition was significantly related to individual perceptual asymmetry during the subsequent lexical decision task. This basal arousal asymmetry was relatively stable across different task conditions. A task-related arousal asymmetry measured at the parietal location during the lexical decision task also made a significant contribution in predicting individual perceptual asymmetry. These two measures of individual arousal asymmetry were able to predict 50% of the variance in perceptual asymmetry. The implications of the results for explaining more wide-ranging individual differences in behavioral style and personality are discussed.     

Power spectral density changes in the EEG during mental arithmetic and eye-opening

Summary The effect of mental arithmetic (standard multiplication, with eyes closed) and eye-opening on the power spectral density of the EEG (recorded bipolarly from occipital and parietal regions) have been compared. The EEG was recorded on magnetic tape from normal subjects, (medical students) in a constant environment and subsequently analysed by an analogue computer (Noratom Instrument for Statistical Analysis and Computation, ISAC).Absolute measurements made from 15 subjects with eyes closed have shown that peaks of power at 10 Hz vary from 9 to 46 V² per Hz. Qualitatively, suppression of power at 10 Hz is greater due to eye-opening than mental arithmetic.Analysis of pooled power spectral density functions from 11 subjects showed that the effect of eye-opening differed significantly from the effect of mental arithmetic at 2.5 and 12.5 Hz. Suppression of lower frequency alpha activity was more pronounced during calculation than during eye-opening. Compared with the eyes closed condition, eye-opening showed a highly significant suppression at 10 and 12.5 Hz (alpha activity) and from 15 to 25 Hz (beta activity). Mental arithmetic induced significant suppression at 7.5 and 10 Hz and from 15 to 30 Hz. Eye-opening enhanced lower frequency activity which calculation suppressed.Variation was greater between first, second and third calculations in pooled power spectral densities than between corresponding eye-opening epochs. It is suggested that these differences in effects of eye-opening and mental arithmetic reflect differences in underlying cerebral activity, rather than that an underlying factor common to both effects may be orbital in origin.     

PET activation studies comparing two speech tasks widely used in surgical mapping

"Automatic" speech, especially counting, is frequently preserved in aphasia, even when word production is severely impaired. Although brain sites and processes for automatic speech are not well understood, counting is frequently used to elicit fluent speech during preoperative and intraoperative cortical mapping for language. Obtaining both behavioral and functional brain imaging measures, this study compared counting with a word production task (generation of animal names), including non-verbal vocalizations and quiet rest as control states, in normal and aphasic subjects. Behavioral data indicated that normal and aphasic groups did not differ in counting or non-verbal vocalizations, but did differ significantly in word production ("naming" animals). Functional brain imaging results on normal subjects using partial least squares analysis of PET rCBF images revealed three significant latent variables (LVs): one for naming and vocalizing, identifying bilateral anterior areas, with left predominating over right; a second LV for naming, identifying left and right frontal and temporal areas. For the third, only marginally significant LV, which was associated with automatic speech alone (counting), right and subcortical sites predominated. For patients, two LVs emerged, identified with naming and vocalization, and corresponding to a variety of cerebral sites; the analysis failed to find a specific latent variable for counting. A comparison between group data for normal subjects and patients suggested that the naming, counting, and vocalization tasks were performed differently by the two groups. These results suggest that word generation as a verbal task is more likely to elicit activity in classical language areas than counting. Further studies are suggested to better understand differences between neurological substrates for non-propositional and automatic speech.     

Testing idiom comprehension in aphasic patients: the effects of task and idiom type

Idiom comprehension in 15 aphasic patients was assessed with three tasks: a sentence-to-picture matching task, a sentence-to-word matching task and an oral definition task. The results of all three tasks showed that the idiom comprehension in aphasic patients was impaired compared to that of the control group, and was significantly affected by the type of task and type of idiom. Whilst performance on the oral definition and sentence-to-picture matching tasks was similarly impaired, the patients performed significantly better on the sentence-to-word matching task. The results confirm the relevance of task and idiom type in drawing conclusions about figurative language interpretation in brain-damaged patients.     

An Acoustic Analysis of Rate of Speech Effects on Vowel Production in Aphasia

The present investigation examined the production of tense and lax vowel duration differences at two speaking rates in the speech of 10 nonfluent aphasics, 8 fluent aphasics, and 10 normal control subjects. Subjects produced four repetitions of each of the vowels [i e æ o u I ε υ Λ] at each speaking rate. Acoustic analyses revealed that subjects in all three groups were able to manipulate overall rate of speech. In addition, normal controls and fluent aphasic subjects produced vowels under the fast rate condition which were significantly shorter than those under the slow rate condition. Despite a change in overall speaking rate, the nonfluent aphasics did not exhibit a significant difference in vowel duration at the two rates of speech, suggesting a deficit in the implementation of this temporal parameter. Both normal controls and fluent aphasic patients produced nonoverlapping distributions of tense and lax vowels at both speaking rates. In contrast, the nonfluent aphasics demonstrated a great deal of overlap in the distribution of tense and lax vowel durations at the fast rate. Results are discussed in relation to the nature of the speech production deficits in nonfluent and fluent aphasic patients.     

The effects of varying attentional demands on the word retrieval skills of adults with aphasia, right hemisphere brain damage, or no brain damage

Adults with mild aphasia, right hemisphere brain damage (RBD), or no brain damage (NBD) provided one-word phrase completions under isolation, focused attention, and divided attention conditions and in response to relatively constrained or unconstrained phrase stems. Despite comparable word retrieval accuracy among groups during the isolation condition, aphasic and RBD groups performed less accurately than the NBD group during focused and divided attention conditions. Across conditions, there were no significant differences between aphasic and RBD groups. Only aphasic subjects demonstrated a significant effect of phrase type, responding more accurately when completing constrained versus unconstrained stimuli. For aphasic and RBD groups, error type analysis indicated that semantic and phonological aspects of word retrieval were influenced by increased attentional demands. These findings suggest that for adults with aphasia or RBD, there is a negative relation between attention impairments and word retrieval abilities.     

Disorders of classificatory activity in aphasia

Two nonverbal tasks of classificatory activity ("class inclusion" and "class intersection") were administered to 46 aphasics, 28 normal controls, 19 nonaphasic left-brain-damaged and 17 right-hemisphere-damaged patients in order to study if aphasic patients are more impaired than nonaphasic brain-damaged patients on these two tasks of elementary logic and if a relationship exists within the aphasic patients between inability to perform the tasks of classifiactory activity and impairment of the semantic-lexical level of integration of language. Results were for the most part in line with expectations because aphasics scored worse than normal controls and nonaphasic brain-damaged patients (even if the difference reached the level of statistical significance only on the test of "class intersection") and within the aphasic patients the worst results were obtained by subjects presenting clear signs of semantic-lexical disintegration.     

Intentional and incidental visual memory as a function of cognitive level and color of the stimulus

Performance of two groups of youngsters, educable mentally retarded (CA 15-5; MA 11-4; IQ 74.3) and those of average ability (CA 10-5; MA 11-3; IQ 109.1) was compared for intentional and incidental visual memory as a function of cognitive level and color of the stimulus. Nonretarded subjects performed significantly better than the retarded ones of equal MA. Both groups performed better with a color than black-white card, and both groups did better on the tasks involving intentional rather than incidental memory.     

Acute responses to locomotor tasks differ according to gait-asymmetry patterns in children with hemiplegic cerebral palsy: An exploratory analysis

This study aimed at determining if differential responses to locomotor tasks in children with spastic hemiplegia occur on account of step-length asymmetry patterns [symmetrical step-length (S-SL); affected side short (AFF_short), and non-affected short (Non-AFF_short)] observed during on-ground walking. Thirty-two children (5–8 years) were assessed for spatial/temporal measures of gait while walking on the ground with self-selected speed. Data from on-ground walking were compared against three locomotor tasks that were examined on a treadmill: self-imposed walking velocity with bodyweight support of 0% (BWS-0%), self-imposed walking velocity with a BWS of 20% (BWS-20%), and fastest walking velocity with a BWS of 20% and a manually-guided response of the non-affected leg (MGR_non-affected). The primary outcome measures were the spatial (step length) and temporal (single-limb support time) symmetry indices. The step-length asymmetry subgroups responded differently to the locomotor tasks. The MGR_non-affected produced spatial symmetry in the S-SL and Non-AFF_short groups and temporal symmetry in the AFF_short group. The BWS-0% and BWS-20% treadmill walking conditions were insufficient to remediate either spatial or temporal walking asymmetry. In conclusion, acute responses to locomotor tasks are not consistent among asymmetry subgroups, suggesting that they might need individual treatment plans. In spite of the differences in walking characteristics between asymmetry subgroups, the improvement in gait-symmetry arose out of changes in affected and non-affected sides together.     

Phonological transformations in Spanish-speaking aphasics

Thirty-seven aphasic patients whose native language is Spanish were divided into four groups: (1) Broca's, (2) Wernicke's, (3) Conduction, and (4) Anomia. Phonological errors produced on repetition and object-naming tasks were analyzed in terms of type of transformation and degree of similarity between target and errors in terms of shared distinctive features. Segmental transformations were of the following types: (1) pure substitution, (2) pure addition, (3) deletion, (4) reduplicative addition (doublet creation)—anticipatory (right to left) or perseverative (left to right), (5) reduplicative substitution (doublet creation)—anticipatory or perseverative, and (6) mutual exchanges. Pure substitutions were the most prevalent, exchanges, the least. Some error types were found to differentiate significantly between aphasic populations. We suggest that different mechanisms may underlie the same error type for different aphasic populations.     

Nonspeech and speech processing skills in patients with aphasia and apraxia of speech

Nonspeech and speech auditory processing skills as well as internal speech processing skills were assessed among four patients with acquired "pure" apraxia of speech, 10 with acquired aphasia, 10 with aphasia plus apraxia of speech, and 11 neurologically normal adults. Fourteen tasks were administered and performances on 68 variables were examined using both nonparametric and parametric analyses controlling for the effects of advancing age and associated hearing loss. In all cases, the "pure" apractic patients performed as normal subjects. Few differences were noted among the performances of the aphasic and aphasic-apractic subjects. Results led to three major conclusions: (1) apraxia of speech is a disorder distinct from aphasia; (2) aphasic individuals, despite locus of lesion, demonstrate disabilities for processing nonspeech and speech materials presented auditorily and for analytically evaluating speech evoked internally; and (3) aphasic individuals demonstrating similar severity levels of language impairment show similar performance patterns for these types of processing tasks, despite locus of lesion or coexistence of apraxia of speech.     

Speech sound errors in patients with conduction and Broca's aphasia

Speech sound errors exhibited by three conduction and three Broca's aphasic patients on naming and word-repetition tasks were subjected to phonemic and subphonemic analyses. In the conduction aphasic patients, errors occurred equally often on consonants and vowels in both the naming and word-repetition tasks, while in the Broca's aphasic patients errors occurred selectively on consonants. Transposition errors occurred almost as often as substitution errors in the conduction aphasic patients, while substitution errors constituted the majority of errors in the Broca's aphasic patients. The Broca's aphasic patients, as compared to the conduction aphasic patients, exhibited a markedly higher number of substitution errors occurring between phonemes separated by a single subphonemic feature on the naming task. On the basis of these findings, it was hypothesized that the differences in the error patterns of the two types of aphasia reflected differences in the underlying mechanisms of the impairment in each type.     

Increased susceptibility of aphasics to a distractor task in the recall of verbal commands

The ability of 15 control, 15 nonaphasic brain-damaged, and 15 aphasic patients to carry out three-word commands on the Token Test was studied under three conditions: no delay, 20-sec unfilled delay, and 20-sec delay filled with a counting task. Only aphasics with mild to moderate comprehension deficit participated in the experiment and their scores in the no-delay condition were not inferior to those of the other two groups. The 20-sec unfilled delay did not bring about a decrement of the performance in any group, while all of them were impaired with 20-sec filled delay. The rate of forgetting was, however, significantly greater in aphasics than in patients without language disorders, even when the scores of the no-delay condition were introduced as covariates in the analysis of the filled-delay condition. The same result was obtained when, in a second experiment, 4 sec elapsed between the end of the command and the beginning of the counting activity. The increased susceptibility of aphasics to the disruptive effect of the distractor task is viewed as following a failure in organizing verbal information, a deficit that may contribute to lowering their comprehension level.