Parameters for vowel substitutions in Broca''s aphasia

Most phonological investigations of aphasic speech have focused on consonants. In this study, the vowel substitutions of five English-speaking Broca's aphasics were investigated with respect to several major explanatory hypotheses. An important possible motivating factor for aphasic substitutions, phonological environment, is an unlikely origin for these errors, since most substitutions occur along the paradigmatic axis. Another prominent hypothesis, markedness, also has no predictive power for the data of this sample. However, an analysis of the five Chomsky and Halle (1968, (The Sound Pattern of English), New York: Harper and Row) vowel features indicates that the two features for vowel height are selectively impaired: There is a strong tendency for lower vowels to replace higher targets. Moreover, the substitution sounds tend to be close to their target sounds along the height axis. Four possible hypotheses are advanced to account for this consistent lowering tendency.     

Studies in social influence: V. Minority influence and conversion behavior in a perceptual task

The effects of influence attempts by a majority and by a minority were examined on both a manifest response level and a latent perceptual level. Female subjects were exposed to a series of blue slides that were consistently labeled as green by a female confederate. The confederate was presented as a member of either a majority or a minority. On each trial, subjects were required to indicate the color of the slide presented and the color of the afterimage perceived on a white screen following removal of the slide. It was predicted that (a) the subject's judgment of the chromatic afterimage would be modified when the influence agent represented a minority, and (b) this modification will be more pronounced when the source of influence is absent than when it is present. The results supported the prediction in both the main study and its replication.     

Task determinants of ear differences in melody processing

In Experiment 1 nonmusicians were presented with dichotic melodies, which differed either on all pitches or by a single note, followed by a set of four binaural melodies. They were asked to recognize among the alternatives only one member of the dichotic pair in the “single-focus” task, and both dichotic melodies in the “double-focus” task. These different attention requirements led to a LEA in the first task which contrasted with the REA observed in the other task when melodies differed by all pitches. A possible confounding (fusion of the common pitches) prevents comparison of the tasks for melodies differing by a single pitch. The role of the extent of melody differences was further investigated in a second experiment by changing melodies on one, two, or three notes. No effect of material was observed on ear asymmetries. Task demands appeared as the most critical determinant of ear differences and are discussed in terms of their particular influence on the adoption of an analytic or holistic processing mode. Male subjects were found to be more responsive than females to analytic processing suggestions.     

Habit reversal treatment: Learning an incompatible response or increasing the subject's awareness?

The elements of the Habit Reversal Treatment Package developed by Azrin and Nunn (1973) to counteract nervous habits were systematically analysed. Fifty nail biters (92% reported biting their nails for more than 5 yr) were randomly assigned to one of the following treatments: Habit Reversal, Habit Reversal and Self-Monitoring, Self-Monitoring, Self-Monitoring and Daily Graph Plotting, Waiting List control, Pictures of both hands were taken prior to the commencement of treatment and at 6 and 12 weeks after treatment termination. The results showed that the four treatment groups improved equally compared with the control subjects. Such data cast doubt on the importance of learning an incompatible response in Habit Reversal Treatment. An alternative explanation based on increasing the subject's awareness is put forward.     

Listening to speech while retaining music: What happens to the right-ear advantage?

On each trial, subjects were played a dichotic pair of syllables differing in the consonant (/ba/, /da/, /ga/) or in the vowel (/ba/, /b?/, /bi/). The pair of syllables was preceded by a melody, or a sentence, and followed by the same or a different melody, or sentence. Subjects either had to retain the first piece of additional material or were free to ignore it. The different combinations of phonemic contrast, additional material, and instruction concerning the additional material were used in different sessions. In each case, the main task of the subjects was to respond to the presence or the absence of the target /ba/ on the ear previously indicated. There was no effect of context on relative ear accuracy, but the right-ear advantage observed for consonants in response latency when subjects retained a sentence gave way to a small nonsignificant left-ear advantage when subjects retained a melody. Right-ear advantage in response latencies was also observed for vowels in the verbal context, but the contextual effect, although in the same direction as for consonants, was very slight. The implications of contextual effects for a theory of the determinants of the auditory laterality effects are discussed.     

Configural conditioning in the CER: Loss of element strength after repeated reinforced compound CS trials

Different groups of rats received different numbers of compound CS (light/noise) conditioning trials in the CER procedure. The amount of suppression evident to the single elements of the compound decreased as a function of the number of previous compound trials. This loss of CR strength was interpreted as a configuring effect. Further experimental comparisons indicated that the configuring effect could not be readily explained in terms of a generalization decrement or a stimulus novelty hypothesis.