Decision deadlines and uncertainty monitoring: the effect of time constraints on uncertainty and perceptual responses

The behavioral uncertainty response has grounded the study of animal metacognition and influenced the study of human psychophysics. However, the interpretation of this response is debated—especially whether it is a behavioral index of metacognition. The authors advanced this interpretation using the dissociative technique of response deadlines. Uncertainty responding, if it is higher level or metacognitive, should depend on a slower, more controlled decisional process and be more vulnerable to time constraints. Humans performed sparse–uncertain–dense or sparse–middle–dense discriminations in which, respectively, they could decline difficult trials or positively identify middle stimuli. Uncertainty responses were sharply and selectively reduced under a decision deadline, as compared to primary perceptual responses (i.e., “sparse,” “middle,” and “dense” responses). This dissociation suggests that the uncertainty response does reflect a higher-level, decisional response. It grants the uncertainty response a distinctive psychological role in its task and encourages an interpretation of this response as an elemental behavioral index of uncertainty that deserves continuing research.     

Discrimination and Reversal Learning by Toddlers Aged 15-23 Months

Few studies have investigated simple discrimination and discrimination reversal learning by children younger than 2 years. Extant research has shown that teaching discrimination reversals may be challenging with this population. We used social reinforcement and correction procedures to teach simple simultaneous discrimination and discrimination reversal tasks involving three pairs of animal pictures displayed in a paper notebook. Participants were eight typically developing toddlers aged 15-23 months. All learned at least one simple discrimination/discrimination reversal problem. Four children learned all problems and showed evidence of learning set formation. Perhaps surprisingly, discrimination reversals were sometimes learned more rapidly than original discriminations. The procedures suggest a potentially efficient methodology for investigating more complex aspects of relational learning in toddlers.

     

Psychoacoustic cues to emotion in speech prosody and music

There is strong evidence of shared acoustic profiles common to the expression of emotions in music and speech, yet relatively limited understanding of the specific psychoacoustic features involved. This study combined a controlled experiment and computational modelling to investigate the perceptual codes associated with the expression of emotion in the acoustic domain. The empirical stage of the study provided continuous human ratings of emotions perceived in excerpts of film music and natural speech samples. The computational stage created a computer model that retrieves the relevant information from the acoustic stimuli and makes predictions about the emotional expressiveness of speech and music close to the responses of human subjects. We show that a significant part of the listeners’ second-by-second reported emotions to music and speech prosody can be predicted from a set of seven psychoacoustic features: loudness, tempo/speech rate, melody/prosody contour, spectral centroid, spectral flux, sharpness, and roughness. The implications of these results are discussed in the context of cross-modal similarities in the communication of emotion in the acoustic domain.     

Disproportionate Representation in Special Education: A Synthesis and Recommendations

Disproportionate representation of minority students in special education remains a very controversial, unresolved issue. This synthesis summarizes historical perspectives and current knowledge about disproportionate representation with respect to: (a) definitions of disproportionate representation and related issues of interpretation; (b) national and state-level estimates of disproportionality for four ethnic groups; (c) legal, policy, research and teacher education responses to disproportionality; and (d) hypothesized causes and predictors of disproportionality. Authors stress the need for: coherent and well-articulated conceptual frameworks, responsible use and representation of data, research dialog that is informed by appreciation of the complex sociopolitical history and current context, and the need for effective advocacy to improve the educational success of minority students.     

Atypical categorization in children with high-functioning autism spectrum disorder

Children with autism spectrum disorder process many perceptual and social events differently from typically developing children, suggesting that they may also form and recognize categories differently. We used a dot pattern categorization task and prototype comparison modeling to compare categorical processing in children with high-functioning autism spectrum disorder and matched typical controls. We were interested in whether there were differences in how children with autism use average similarity information about a category to make decisions. During testing, the group with autism spectrum disorder endorsed prototypes less and was seemingly less sensitive to differences between to-be-categorized items and the prototype. The findings suggest that individuals with high-functioning autism spectrum disorder are less likely to use overall average similarity when forming categories or making categorical decisions. Such differences in category formation and use may negatively impact processing of socially relevant information, such as facial expressions. A supplemental appendix for this article may be downloaded from http://pbr.psychonomic-journals.org/content/supplemental.     

National leadership for children and youth with serious emotional disturbance: Progress and prospects

Despite the federal mandate to identify and provide appropriate educational and related services to children and youth with serious emotional disturbance (SED), the national profile portrays exceptionally low rates of identification; unacceptably low rates of school completion; high rates of placement in segregated environments; evidence that economic and demographic factors substantially affect identification, placement, and school completion; and a mixed, although mostly discouraging picture of outcomes after leaving the educational system. Recent national leadership, comprised of strategic planning, research, and demonstration initiatives has attained considerable momentum and is intended to improve outcomes for children with SED. Significant changes are anticipated as a result of the upcoming reauthorization of the statute governing special education and related services. These changes reflect a 20 year perspective regarding the benefits and shortcomings of current eligibility criteria and discretionary initiatives for improving outcomes for children with disabilities. The manner in which these changes may affect prospects for better serving children with SED is discussed.     

Refining the visual-cortical hypothesis in category learning

Participants produce steep typicality gradients and large prototype-enhancement effects in dot-distortion category tasks, showing that in these tasks to-be-categorized items are compared to a prototypical representation that is the central tendency of the participant’s exemplar experience. These prototype-abstraction processes have been ascribed to low-level mechanisms in primary visual cortex. Here we asked whether higher-level mechanisms in visual cortex can also sometimes support prototype abstraction. To do so, we compared dot-distortion performance when the stimuli were size constant (allowing some low-level repetition-familiarity to develop for similar shapes) or size variable (defeating repetition-familiarity effects). If prototype formation is only mediated by low-level mechanisms, stimulus-size variability should lessen prototype effects and flatten typicality gradients. Yet prototype effects and typicality gradients were the same under both conditions, whether participants learned the categories explicitly or implicitly and whether they received trial-by-trial reinforcement during transfer tests. These results broaden out the visual-cortical hypothesis because low-level visual areas, featuring retinotopic perceptual representations, would not support robust category learning or prototype-enhancement effects in an environment of pronounced variability in stimulus size. Therefore, higher-level cortical mechanisms evidently can also support prototype formation during categorization.     

Differential Reinforcement in Simple Discrimination Learning in 10- to 20-Month-Old Toddlers

The Psychological Record - The present study examined two procedures for teaching simple discrimination to six toddlers aged 10- to 20-months. A pair of toys was displayed in the windows of an...