Production deficits in aphasia: A voice-onset time analysis

An experimental study was conducted to examine phonetic and phonemic deficits in the speech production of aphasics. Subjects included four Broca's aphasics, four Conduction aphasics, five Wernicke's aphasics, one nonaphasic dysarthric patient, and four normal controls. The subjects read a list of words containing word-initial stop consonants which were subsequently measured acoustically for voice-onset time. The results showed that Broca's aphasics exhibit a more severe production disorder than Conduction aphasics who in turn exhibit a more severe disorder than Wernicke's aphasics, in accord with clinical observations. In addition, although Broca's aphasics produced both phonetic and phonemic errors, the results showed that they have a pervasive phonetic disorder which affects their correct target productions as well as the total number of phonetic errors produced. This deficit however seems to be a speech deficit rather than a low-level motor control problem. In contrast, the Wernicke's aphasics show a deficit characterized by isolated phonemic mistargeting errors. Finally, the pattern of productions for the Conduction aphasics indicates that some patients show a predominantly phonetic disorder similar to the Broca's aphasics and others show predominantly a phonemic disorder similar to the Wernicke's aphasics.     

A reconstructive-processing interpretation of the recognition failure phenomenon

The generality of the recognition failure phenomenon was the primary basis for the present research. It was hypothesized that the phenomenon obtains whenever an insufficient degree of compatibility exists between the task demands at recognition and those present during study. Experiments 1 and 2 demonstrated that, despite a recognition task that was incompatible to conditions of encoding, subjects could actively reconstruct aspects of the initial situation, and hence recognition failure was minimized. It was assumed that the stimulus material — categorized word pairs — facilitated this reconstructive process. Experiment 3 was designed specifically to examine further the reconstructive process as well as recognition failure. The results indicated that (a) the nature of this process could be mathematically predicted, and (b) subjects seldom failed to recognize words they recalled. The results of the present study strongly suggest an important boundary condition of the phenomenon of recognition failure. Moreover, Tulving and Wiseman's (1975) quadratic function could not predict accurately the obtained magnitude of recognition failure.     

Self-consciousness and reactance

Two studies examined the effects of dispositional self-consciousness on reactance. In Experiment 1, men who were high in private self-consciousness displayed greater reactance responses to a coercive communication attempt (as reflected by attitude reversal) than did men lower in private self-consciousness. In contrast, the effect of public self-consciousness in this context was to inhibit the expression of reactance. In Experiment 2, women high in private self-consciousness exhibited greater reactance responses to a self-imposed threat to their freedom of choice (as reflected by equivocation over two choice alternatives) than did women lower in private self-consciousness. The effect of public self-consciousness in this context was negligible. These findings replicate and extend a previous self-awareness and reactance finding; they provide additional evidence that manipulated self-awareness and dispositional self-consciousness converge on the same psychological entity; and they provide additional evidence that there are important differences between the dimensions of private and public self-consciousness.     

Retention of verbal information by rehearsal in relation to the fluency of verbal output in aphasia

The purpose of the present study was to determine if aphasic subject groups differentiated by the fluency of their verbal output employed rehearsal as a strategy for maintaining verbally coded information in primary memory. A task based upon the Brown-Peterson paradigm was administered to 10 fluent aphasic patients, 10 nonfluent aphasic patients, 10 right-brain-damaged patients, and 10 nonneurological patients. The findings indicate that the nonfluent aphasic patients did not rehearse the verbal information while the fluent aphasic, right-brain-damaged, and nonneurological patients did rehearse. In addition, both fluent and nonfluent aphasic patients encoded significantly less information into the memory system initially and performed worse on the task overall than right-brain-damaged and nonneurological patients.     

Affect as a mediator of attributional egotism

A three-stage model of the relationships among achievement outcomes, outcome-related affect, attribution, and emotion is tested in two studies. It is suggested that success and failure elicit positive and negative affective states due to prior conditioning. These affective states then lead to an attribution process that serves to defend and enhance self-esteem. Next, emotional labels are chosen that are consistent with the affective states and the attributions. Two studies were designed to test the proposed relationships among achievement outcomes, affective states, and attributions. In the first study, subjects received information indicating that they were strongly or mildly aroused as a result of receiving outcome feedback on an achievement task. The results indicated that low arousal reduced egotistical attributions to internal factors. In the second study, subjects either succeeded or failed on an achievement task. Half of the subjects were provided with an opportunity to misattribute the arousal elicited by their outcomes to an irrelevant source. Subjects in the misattribution condition made less egotistical attributions to external factors than subjects who were given no opportunity to misattribute their arousal. The results of both studies suggest that outcome-related affect mediates the relationship between outcomes and attributions in achievement situations.     

Spontaneous configuring to a tone-light compound using appetitive training

Rats were trained to bar-press for water in the presence of a simultaneous compound tone-light stimulus using a discrete-trial procedure. Different groups were given between 300 and 3900 trials. When subsequently tested in extinction, all rats showed consistent levels of responding to the compound stimulus but responding to the tone and light components declined as a function of number of training trials. This is a demonstration of spontaneous configuring. Two other experiments showed that with similar procedures generalization from a component of the training stimulus to other values on the same continuum decreases with increased training with the compound stimulus. It was concluded that configuring and generalization from a single stimulus involve the same processes.     

Blocking acquisition of the rabbit's nictitating membrane response to serial conditioned stimuli

Three experiments demonstrated that prior training with one stimulus (CS1) would block acquisition of the rabbit's nictitating membrane response (NMR) to another stimulus (CS2) which was more contiguous to the US during serial compound training (CS1-CS2-US). Specifically, the CS1-US interval was 800 msec, which produces only a modest rate of CR acquisition, while the CS2-US interval was 400 msec, which is an optimal value for the NMR preparation. Experiment 1 demonstrated blocking when CS1 overlapped CS2, and Experiment 3 demonstrated blocking when CS1 and CS2 were presented in a strictly sequential fashion. Experiment 2 showed that the magnitude of blocking in the serial compound was comparable to that obtained in a simultaneous compound in which both the CS1-US and CS2-US intervals were 800 msec, thus making CS2 less contiguous with the US than in the serial compound. Moreover, the level of responding to CS2 in all serial compound groups (blocking and control) was lower than in the simultaneous compound groups. The present findings provide further evidence that the associative consequences of CS-US contiguity can be highly attenuated by processes of attention or competition for associative strength.     

The development of handedness and dichotic ear listening asymmetries in relation to school achievement: A longitudinal study

To assess the development of dichotic ear asymmetries and handedness, 208 male school children were evaluated in kindergarten and at Grades 2 and 5 (ages 66, 92, and 130 months of age, respectively) with a dichotic listening task and a hand preference test. The Wide Range Achievement Test (WRAT) also was administered at each of the three grade levels. There was significant variability in handedness scores over time only for those subjects whose scores at initial testing, that is, in kindergarten, identified them as non-right-handers. Both right and left handers had a significant increase in dichotic listening scores over time; however, only right handers had a significant right ear advantage at each evaluation. Regression analyses showed that combined hand preference scores and ear recall scores at each probe when combined accounted for almost 44% of the variance in WRAT achievement scores at Grade 5. Ear asymmetry scores, however, were not predictive of school achievement.     

Analgesic and opioid involvement in the shock-elicited activity and escape deficits produced by inescapable shock

Three experiments examined the involvement of analgesic processes and endogenous opioids in the production of the shuttlebox escape acquisition and unconditioned activity deficits which follow exposure to inescapable shock. Experiment 1 found that the opiate antagonist naltrexone administered before the inescapable shock session interfered with the shuttlebox escape acquisition deficit which would normally follow. Experiment 2 found naltrexone to completely prevent the unconditioned activity deficit. The final experiment revealed that dexamethasone, a synthetic glucocorticoid which abolishes the analgesia produced by inescapable shock, reversed the activity deficit. These results indicate that endogenous opioids may be involved in the production of both the escape acquisition and activity deficits. They also suggest that the analgesia produced by these opioids may participate in the mediation of the activity deficit, even though analgesia is not involved in producing the shuttlebox acquisition deficit.