Acoustic feature analysis in the perception of voicing contrasts

Various types of acoustic cues have been shown to signal voicing contrasts in initial prestressed stop consonants. Two of the most important of these cues are the time interval between the release burst and the onset of voicing (voice onset time) and the duration of voiced transitions. In the present experiment, a selective adaptation procedure was used to investigate possible feature extraction mechanisms which underlie the perception of voicing. Subjects first identified either of two series of test stimuli, [ba-p^ha) or [ga-k^ha]. Next they listened to repeated presentations of an adapting stimulus and then again identified the original test series. Adapting stimuli having the same value of voice onset time but different voiced transition durations produced differential (and sometimes opposite) effects on the identification of the test stimuli. In every case, the adapting stimulus with the greater duration of voiced transitions led to larger reduction in voiced responses or to a smaller increase in voiceless responses. These results are incompatible with models of voicing perception based strictly on detectors for voice onset time. The results also suggest that the adaptation effect occurs at a point in the system prior to the actual phonetic decision.     

Aging and temporal discrimination of brief auditory intervals

Summary In a duration-discrimination experiment, young adults (mean age = 25.1), middle-aged adults (mean age = 45.5), and older adults (mean age = 64.6) were presented with two very brief auditorily marked intervals per trial, and their task was to decide which of the two was longer in duration. An adaptive psychophysical procedure was used to determine difference thresholds in relation to a constant standard interval of 50 ms. It was found that duration-discrimination performance was unaffected by age; all three age groups yielded a difference threshold of approximately 17 ms. It was concluded that the ability to discriminate durations of very brief auditory intervals appears to be based on an underlying timing mechanism that does not slow down with advancing adult age.     

Delayed working memory consolidation during the attentional blink

After the detection of a target (T1) in a rapid stream of visual stimuli, there is a period of 400–600 msec during which a subsequent target (T2) is missed. This impairment in performance has been labeled the attentional blink. Recent theories propose that the attentional blink reflects a bottleneck in working memory consolidation such that T2 cannot be consolidated until after T1 is consolidated, and T2 is therefore masked by subsequent stimuli if it is presented while T1 is being consolidated. In support of this explanation, Giesbrecht & Di Lollo (1998) found that when T2 is the final item in the stimulus stream, no attentional blink is observed, because there are no subsequent stimuli that might mask T2. To provide a direct test of this explanation of the attentional blink, in the present study we used the P3 component of the event-related potential waveform to track the processing of T2. When T2 was followed by a masking item, we found that the P3 wave was completely suppressed during the attentional blink period, indicating that T2 was not consolidated in working memory. When T2 was the last item in the stimulus stream, however, we found that the P3 wave was delayed but not suppressed, indicating that T2 consolidation was not eliminated but simply delayed. These results are consistent with a fundamental limit on the consolidation of information in working memory.     

Affective personality differences in neural processing efficiency confirmed using fMRI

To test for a relation between individual differences in personality and neural-processing efficiency, we used functional magnetic resonance imaging (fMRI) to assess brain activity within regions associated with cognitive control during a demanding working memory task. Fifty-three participants completed both the self-report behavioral inhibition sensitivity (BIS) and behavioral approach sensitivity (BAS) personality scales and a standard measure of fluid intelligence (Raven’s Advanced Progressive Matrices). They were then scanned as they performed a three-back working memory task. A mixed blocked/ event-related fMRI design enabled us to identify both sustained and transient neural activity. Higher BAS was negatively related to event-related activity in the dorsal anterior cingulate, the lateral prefrontal cortex, and parietal areas in regions of interest identified in previous work. These relationships were not explained by differences in either behavioral performance or fluid intelligence, consistent with greater neural efficiency. The results reveal the high specificity of the relationships among personality, cognition, and brain activity. The data confirm that affective dimensions of personality are independent of intelligence, yet also suggest that they might be interrelated in subtle ways, because they modulate activity in overlapping brain regions that appear to be critical for task performance.     

Visual Search Remains Efficient When Visual Working Memory is Full

Many theories of attention have proposed that visual working memory plays an important role in visual search tasks. The present study examined the involvement of visual working memory in search using a dual-task paradigm in which participants performed a visual search task while maintaining no, two, or four objects in visual working memory. The presence of a working memory load added a constant delay to the visual search reaction times, irrespective of the number of items in the visual search array. That is, there was no change in the slope of the function relating reaction time to the number of items in the search array, indicating that the search process itself was not slowed by the memory load. Moreover, the search task did not substantially impair the maintenance of information in visual working memory. These results suggest that visual search requires minimal visual working memory resources, a conclusion that is inconsistent with theories that propose a close link between attention and working memory.     

MRI-Assessed Volume of Cerebellum Correlates with Associative Learning

Richard F. Thompson's cerebellar model of classical eyeblink conditioning highlights Purkinje cells in cerebellar cortex and principal cells in the deep cerebellar nucleus as the integrating cells for acquisition of conditioned responses (CRs). CR acquisition is significantly slower in rabbits with lesions to cerebellar cortex and in Purkinje cell-deficient mice that lose all cerebellar cortical Purkinje cells. Purkinje cells are the largest neurons in the cerebellum and contribute significantly to cerebellar volume. Magnetic resonance imaging (MRI) was used to assess cerebellar volume in humans. Cerebellar volume was related to eyeblink conditioning (400-ms delay procedure) in 8 adults (21-35 years) and compared to 8 older adults (77-95 years) tested previously (Woodruff-Pak, Goldenberg, Downey-Lamb, Boyko, & Lemieux, 2000). In the young adult sample, there was a high correlation between percentage of CRs in a session and cerebellar volume (corrected for total intracranial volume [TIV], r =.58, p =.066). There were statistically significant age differences in cerebellar volume, t(14) = 8.96, p <.001, and percentage of CRs, t(14) = 3.85, p <.002, but no age difference in TIV. Combining the young and older adult sample, the correlation between percentage of CRs and cerebellar volume (corrected for TIV) was.832 (p <.001). Cerebellar volume showed age-related deficits likely due to Purkinje cell loss. Individual differences in classical eyeblink conditioning are associated with differences in cerebellar volume, supporting Thompson's model of a cerebellar cortical role in facilitating this form of associative learning.     

Responses to Depression in Children: Reconceptualizing the Relation Among Response Styles

We propose that researchers should utilize ratio scores when examining the response styles theory rather than examine each of the response styles separately. Higher ratio scores indicate a higher probability of engaging in ruminative, as opposed to distracting and problem solving, behaviors. In Phase One, we examined the factor structure and reliability of the Children's Response Styles Questionnaire (CRSQ) in a sample of 287 third through sixth grade schoolchildren. A two factor solution was obtained: (1) Rumination and (2) Distraction and Problem Solving. Both factors exhibited strong psychometric properties. In Phase Two, 140 children completed the CRSQ and the Children's Depression Inventory (CDI). Six weeks later, children completed the CDI. Confirmatory factor analysis indicated that the two-factor solution fit the data well. In line with hypotheses, CRSQ ratio scores were more strongly associated with CDI residual change scores than were either CRSQ rumination or distraction and problem solving scores.     

Beurteilerübereinstimmung von Psychotherapie-Gutachtern

The access to outpatient psychotherapy in Germany is regulated by an application and expert opinion procedure in a peer-review system. In an external assessment procedure, the application of each patient is considered concerning the existence of a mental disorder, a positive prognosis as well as the adequacy of the chosen therapy rationale. The present paper examines the reliability of this procedure by reanalysing the data from three studies on interrater agreement in the expert opinions about psychoanalytic/psychodynamic therapy, behaviour therapy or child and youth behaviour therapy. In the study of Rudolf et al. (2002) 48 experts re-examined two already assessed cases, in the studies of Sulz et al. (2003) as well as Sulz and Peterander (2004) each of 30 and respectively 7 experts had judged five non selected or seven selected applications. The interrater agreement was calculated using the kappa coefficient by Fleiss for the agreement among many raters, which tests the observed agreement probability against the expected agreement probability that would occur by chance. The level of agreement among the experts differs between 46% and 70%. With the chosen method it is mostly not possible to show that there is a significant higher agreement than by chance. The generalizability of the results to the usual assessment procedure is discussed as well as their potential for the advancement of the application procedure and expert peer-review system.     

The dynamics of empirically derived factors in the therapeutic relationship

The therapeutic relationship is the source of major concepts in psychoanalytic clinical theory. Such concepts as resistance, transference, countertransference, and the alliance are fundamental, even though there may be shifts in meaning between theoretical schools and clinical contexts. In the clinical psychoanalytic literature, disagreement exists over the nature of the alliance and its essential components. Empirical studies using reliable patient, therapist, and observer scales to assess the alliance demonstrate a correlation with psychotherapeutic gains. In the study reported here, thirteen patients were followed for 6 to 33 months of psychodynamic psychotherapy, during which time their views of the therapeutic relationship were assessed, and several experiential measures taken, all on a weekly basis. Statistical analyses reveal that the therapeutic relationship, as reflected in the patients' weekly responses to the St. Louis Therapeutic Relationship Rating Scale, has four distinct components: therapeutic alliance, resistance, transference love, and negative transference. On a week-by-week basis, the therapeutic alliance was the strongest predictor of improvement in patient-reported general adjustment, as reflected in such areas as self-esteem, positive affect, social relations, work productivity, satisfaction, and optimism. Time plots of the variables show the typical time course for the components of the therapeutic relationship, as well as for improvement on the experiential variables. Results indicate that the therapeutic alliance, transference, and resistance are central components of the psychotherapeutic relationship, which in turn predict the ongoing life experience of the patient.