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Shiffrin and Schneider (1977) demonstrated that highly efficientmemory- and visual-search performance could be achievedthrough consistent item-to-response mapping (CM) training. It istheorized that subjects shifted from relying on working memory tolearned item-response associations in long-term memory (Logan,1988). The theory was tested and explored mostly throughbehavioral experiments and computational modeling. In a recentseries of articles involving visual search (e.g. Woodman et al,2013; Carlisle et al. 2011), Woodman and colleagues found thatthe contralateral-delay activity (CDA) of human event-relatedpotentials is related to the maintenance of information in visualworking memory and that the magnitude of the CDA decreaseswhen target information is stored in long-term memory. Weemployed the CDA and other neural measures to study the natureof memory retrieval in CM memory search tasks. We observed asignificant reduction in the magnitude of the CDA in CM trainingcompared to a control condition in which item-response mappingsvaried from trial to trial (VM). The results provided convergingevidence supporting the classic theoretical interpretation of thebases for CM and VM memory search. The results also raisedinteresting questions concerning the detailed interpretation ofCDA.

A previous experiment tested subjects' new/old judgments of previously-studied faces, distractors, and morphs between pairs of studied parents. We examine the extent to which models based on principal component analysis (eigenfaces) can predict human recognition of studied faces and false alarms to the distractors and morphs. We also compare eigenface models to the predictions of previous models based on the positions of faces in a multidimensional "face space" derived from a multidimensional scaling (MDS) of human similarity ratings. We find that the error in reconstructing a test face from its position in an "eigenface space" provides a good overall prediction of human familiarity ratings. However, the model has difficulty accounting for the fact that humans false alarm to morphs with similar parents more frequently than they false alarm to morphs with dissimilar parents. We ascribe this to the limitations of the simple reconstruction error-based model. We then outline preliminary work to improve the fine-grained fit within the eigenface-based modeling framework, and discuss the results' implicadons for exemplar- and face space-based models of face processing.

Perceptual tasks such as object matching, mammogram interpretation, mental rotation, and satellite imagery change detection often require the assignment of correspondences to fuse information across views. We apply techniques developed for machine translation to the gaze data recorded from a complex perceptual matching task modeled after fingerprint examinations. The gaze data provide temporal sequences that the machine translation algorithm uses to estimate the subjects' assumptions of corresponding regions. Our results show that experts and novices have similar surface behavior, such as the number of fixations made or the duration of fixations. However, the approach applied to data from experts is able to identify more corresponding areas between two prints. The fixations that are associated with clusters that map with high probability to corresponding locations on the other print are likely to have greater utility in a visual matching task. These techniques address a fundamental problem in eye tracking research with perceptual matching tasks: Given that the eyes always point somewhere, which fixations are the most informative and therefore are likely to be relevant for the comparison task? (Contains 5 figures and 1 table.)

Despite a profusion of popular misinformation about the left brain and right brain, there are functional differences between the left and right cerebral hemispheres in humans. Evidence from split-brain patients, individuals with unilateral brain damage, and neuroimaging studies suggest that each hemisphere may be specialized for certain cognitive processes. One way to easily explore these hemispheric asymmetries is with the divided visual field technique, where visual stimuli are presented on either the left or right side of the visual field and task performance is compared between these two conditions; any behavioral differences between the left and right visual fields may be interpreted as evidence for functional asymmetries between the left and right cerebral hemispheres. We developed a simple software package that implements the divided visual field technique, called the Lateralizer, and introduced this experimental approach as a problem-based learning module in a lower-division research methods course. Second-year undergraduate students used the Lateralizer to experimentally challenge and explore theories of the differences between the left and right cerebral hemispheres. Measured learning outcomes after active exploration with the Lateralizer, including new knowledge of brain anatomy and connectivity, were on par with those observed in an upper-division lecture course. Moreover, the project added to the students' research skill sets and seemed to foster an appreciation of the link between brain anatomy and function. (Contains 4 figures and 1 table.)

The authors tested the role of individual items in recognition memory using a forced-choice paradigm with face stimuli. They constructed distractor stimuli using morphing procedures that were similar to two parent faces and then compared a studied morph against an unstudied morph that was similar to two studied parents. The similarity of the parent faces was carefully balanced so that the choosing rates for the studied and unstudied morphs were approximately equal. Despite being equally likely to choose the studied and the unstudied morph, participants were systematically more confident when choosing the studied morph. This result is incompatible with Gaussian signal detection theory, even with unequal variances for targets and distractors. The authors propose an extension of an extant sampling model, SimSample, which provides a qualitative and quantitative account of the confidence and recognition dissociation. The results suggest that observers make contact with individual items when making recognition judgments with faces and that the structure of the sampling and decision process naturally leads to this dissociation of confidence and recognition. (Contains 2 tables, 7 figures, and 2 footnotes.)

Describes a modified implementation of an instructional strategy known as problem-based learning (PBL) in an introductory cognitive neuroscience course. Discusses the principles of PBL found to be effective and demonstrates how these principles fostered continued restructuring of the course. (EV)

Purpose: To examine age-related differences in auditory speech recognition and visual text recognition performance for parallel sets of stimulus materials in the auditory and visual modalities. In addition, the effects of variation in rate of presentation of stimuli in each modality were investigated in each age group. Method: A mixed-model design was used in which 3 independent groups (13 young adults with normal hearing, 10 elderly adults with normal hearing, and 16 elderly hearing-impaired adults) listened to auditory speech tests (a sentence-in-noise task, time-compressed monosyllables, and a speeded-spelling task) and viewed visual text-based analogs of the auditory tests. All auditory speech materials were presented so that the amplitude of the speech signal was at least 15 dB above threshold through 4000 Hz. Results: Analyses of the group data revealed that when baseline levels of performance were used as covariates in the group analyses the only significant group difference was that both elderly groups performed worse than the young group on the auditory speeded-speech tasks. Analysis of individual data, using correlations, factor analysis, and linear regression, was generally consistent with the group data and revealed significant, moderate correlations of performance for similar tasks across modalities, but stronger correlations across tasks within a modality. This suggests that performance on these tasks was mediated bath by a common underlying factor, such as cognitive processing, as well as modality-specific processing. Conclusion: Performance on measures of auditory processing of speech examined here was closely associated with performance on parallel measures of the visual processing of text obtained from the same participants. Young and older adults demonstrated comparable abilities in the use of contextual information in each modality, but older adults, regardless of hearing status, had more difficulty with fast presentation of auditory speech stimuli than young adults. There were no differences among the 3 groups with regard to the effects of presentation rate far the visual recognition of text, at least for the rates of presentation used here. KEY WORDS: hearing loss, central auditory processing, time-compressed Speech, speech understanding, aging, It is well known that as adults age, they typically lose the ability to hear high-frequency sounds (e.g., Corso, 1963; Gates, Cooper, Kannel, & Miller, 1990; Glorig & Roberts, 1965; [...]