Human listeners provide insights into echo features used by dolphins (Tursiops truncatus) to discriminate among objects

Echolocating bottlenose dolphins (Tursiops truncatus) discriminate between objects on the basis of the echoes reflected by the objects. However, it is not clear which echo features are important for object discrimination. To gain insight into the salient features, the authors had a dolphin perform a match-to-sample task and then presented human listeners with echoes from the same objects used in the dolphin's task. In 2 experiments, human listeners performed as well or better than the dolphin at discriminating objects, and they reported the salient acoustic cues. The error patterns of the humans and the dolphin were compared to determine which acoustic features were likely to have been used by the dolphin. The results indicate that the dolphin did not appear to use overall echo amplitude, but that it attended to the pattern of changes in the echoes across different object orientations. Human listeners can quickly identify salient combinations of echo features that permit object discrimination, which can be used to generate hypotheses that can be tested using dolphins as subjects.     

Speed, accuracy, and serial order in sequence production

The production of complex sequences like music or speech requires the rapid and temporally precise production of events (e.g., notes and chords), often at fast rates. Memory retrieval in these circumstances may rely on the simultaneous activation of both the current event and the surrounding context (Lashley, 1951). We describe an extension to a model of incremental retrieval in sequence production (Palmer & Pfordresher, 2003) that incorporates this logic to predict overall error rates and speed-accuracy trade-offs, as well as types of serial ordering errors. The model-assumes that retrieval of the current event is influenced by activations of surrounding events. Activations of surrounding events increase over time, such that both the accessibility of distant events and overall accuracy increases at slower production rates. The model's predictions were tested in an experiment in which pianists performed unfamiliar music at 8 different tempi. Model fits to speed-accuracy data and to serial ordering errors support model predictions. Parameter fits to individual data further suggest that working memory contributes to the retrieval of serial order and overall accuracy is influenced in addition by motor dexterity and domain-specific skill.     

A Case Study of the Coping Power Program for Angry and Aggressive Youth

This paper illustrates the application of the Coping Power program with an 11-year-old boy and his father. Coping Power is a manualized preventive intervention for school-age children at-risk for disruptive and delinquent behavior. Cognitive-behavioral techniques are taught in separate child and parent groups to improve children’s social and emotional competencies. This case study highlights the core content of the Coping Power child and parent intervention components, the contextual social cognitive risk factors that the program targets, and the empirical support for the program’s effectiveness.     

Anxiety sensitivity, conscious awareness and selective attentional biases in children

The current study investigated whether physical anxiety sensitivity (AS) is associated with selective attentional biases to affective stimuli in children. The dot-probe paradigm was used to examine the deployment of attention towards words pertaining to anxiety symptomatology, socially threatening words, and positive words, in samples of 8-10-year-old children. Word pairs were presented under both masked and unmasked conditions. Irrespective of masking, children high in physical AS displayed an attentional vigilance for emotional words relative to neutral words, whereas those low in physical AS displayed a relative avoidance of such material. The results of this study are interesting as they not only suggest the presence of automatic AS-related biases in childhood, but that this is a general emotionality bias rather than one related to specific anxiety-related stimuli.     

The role of orthography in speech production revisited

The language production system of literate adults comprises an orthographic system (used during written language production) and a phonological system (used during spoken language production). Recent psycholinguistic research has investigated possible influences of the orthographic system on the phonological system. This research has produced contrastive results, with some studies showing effects of orthography in the course of normal speech production while others failing to show such effects. In this article, we review the available evidence and consider possible explanations for the discrepancy. We then report two form-preparation experiments which aimed at testing for the effects of orthography in spoken word-production. Our results provide clear evidence that the orthographic properties of the words do not influence their spoken production in picture naming. We discuss this finding in relation to psycholinguistic and neuropsychological investigations of the relationship between written and spoken word-production.     

A Comparison of Batterers to Nonbatterers on Behavioral and Self-Reports Measures of Control

This study compared batterers to nonbatterers on self-report and behavioral measures of perceived control and desire for control. Differences were found for perceived control over general life events (batterers greater than nonbatterers), but not perceived control over relationship conflict or desire for control. Batterers low in desire for control and in perceived control over relationship conflicts reported higher levels of physical abuse. Perceived control was manipulated using Burger, Brown, & Allen's (1983 ) behavioral choice task. Batterers who were given no choice reported increased negative affect. Batterers appear to respond to loss of control with negative affect, which may be a factor contributing to abuse perpetration. These results highlight the complexity of the relationship of perceived control and intimate partner violence.     

The effect of aging in recollective experience: the processing speed and executive functioning hypothesis

This study was designed to investigate the effects of aging on consciousness in recognition memory, using the Remember/Know/Guess procedure (Gardiner, J. M., & Richarson-Klavehn, A. (2000). Remembering and Knowing. In E. Tulving & F. I. M. Craik (Eds.), The Oxford Handbook of Memory. Oxford University Press.). In recognition memory, older participants report fewer occasions on which recognition is accompanied by recollection of the original encoding context. Two main hypotheses were tested: the speed mediation hypothesis (Salthouse, T. A. (1996). The processing-speed theory of adult age differences in cognition. Psychological Review, 3, 403–428) and the executive-aging hypothesis (West, R. L. (1996). An application of prefrontal cortex function theory to cognitive aging. Psychological Bulletin, 120, 272–292). A group of young and a group of older adults took a recognition test in which they classified their responses according to Gardiner, J. M., & Richarson-Klavehn, A. (2000). Remembering and Knowing. In E. Tulving & F. I. M. Craik (Eds.), The Oxford Handbook of Memory. Oxford University Press. remember-know-guess paradigm. Subsequently, participants completed processing speed and executive function tests. The results showed that among the older participants, R responses decreased, but K responses did not. Moreover, a hierarchical regression analysis supported the view that the effect of age in recollection experience is determined by frontal lobe integrity and not by diminution of processing speed.     

Dissimilarity is used as evidence of category membership in multidimensional perceptual categorization: a test of the similarity-dissimilarity generalized context model

In exemplar models of categorization, the similarity between an exemplar and category members constitutes evidence that the exemplar belongs to the category. We test the possibility that the dissimilarity to members of competing categories also contributes to this evidence. Data were collected from two 2-dimensional perceptual categorization experiments, one with lines varying in orientation and length and the other with coloured patches varying in saturation and brightness. Model fits of the similarity-dissimilarity generalized context model were used to compare a model where only similarity was used with a model where both similarity and dissimilarity were used. For the majority of participants the similarity-dissimilarity model provided both a significantly better fit and better generalization, suggesting that people do also use dissimilarity as evidence.     

Contralateral visual search deficits following TMS

Transcranial magnetic stimulation of posterior parietal vs. superior temporal sites cause differential effects on conventional conjunction vs. feature search tasks, respectively. We now report that when a decision has to be made on the target's left/right location, different lateralized deficits emerge in these two cases. With full‐field arrays, we found a specific PPC search deficit for contralateral space. With smaller, structured arrays presented in left or right hemispace, we found a specific STG deficit for contralateral parts of the array.