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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; [...]

In the pattern comparison disciplines such as fingerprints, footwear, and toolmarks, the results of a comparison are communicated by examiners in the form of categorical conclusions such as Identification or Exclusion. These statements have been criticized as requiring knowledge of prior probabilities by the examiners and being overinterpreted by laypersons. Alternative statements based on strength‐of‐support language have been proposed. The current study compares traditional conclusion scales against strength‐of‐support scales to determine how these new statements might be used by examiners in casework. Each participant completed 60 comparisons within their discipline, which were designed to approximate casework conditions, using either a traditional or a strength‐of‐support conclusion scale. The scale used on each trial was randomly assigned, and participants knew the scale for that trial as they began the comparison. Fingerprint examiners were much less likely to use Extremely Strong Support for Common Source than Identification. Footwear examiners treated the traditional and strength‐of‐support scales similarly, but toolmark examiners were much less likely to use Extremely Strong Support for Common Source than Identification, similar to fingerprint examiners. A separate group of fingerprint examiners used Identification less often when an expanded scale was available. The results demonstrate that expanded scales may result in the highest conclusion category being used less often by examiners when other alternatives are possible, and the term "extremely strong support" may introduce risk aversion on the part of examiners. [ABSTRACT FROM AUTHOR]

Fingerprint examiners maintain decision thresholds that represent the amount of evidence required for an identification or exclusion conclusion. As measured by error rate studies (Proc Natl Acad Sci USA. 2011;108(19):7733–8), these decision thresholds currently exhibit a preference for preventing erroneous identification errors at the expense of preventing erroneous exclusion errors. The goal of this study is to measure the decision thresholds for both fingerprint examiners and members of the general public, to determine whether examiners are more risk averse than potential jury members. To externally measure these decision thresholds, subjects manipulated decision criteria in a web‐based visualization that reflects the trade‐offs between erroneous identification decisions and erroneous exclusion decisions. Data from fingerprint examiners and the general public were compared to determine whether both groups have similar values as expressed by the placement of the decision criteria. The results of this study show that fingerprint examiners are more risk averse than members of the general public, although they align with error rate studies of fingerprint examiners. Demographic data demonstrate those factors that may contribute to differences in decision criterion placement, both between the two groups and between individuals within a group. The experimental methods provide a rich framework for measuring, interpreting, and responding to the values of society as applied to forensic decision‐making. [ABSTRACT FROM AUTHOR]

Latent fingerprint examiners sometimes come to different conclusions when comparing fingerprints, and eye-gaze behavior may help explain these outcomes. missed identifications (missed IDs) are inconclusive, exclusion, or No Value determinations reached when the consensus of other examiners is an identification. To determine the relation between examiner behavior and missed IDs, we collected eye-gaze data from 121 latent print examiners as they completed a total 1444 difficult (latent-exemplar) comparisons. We extracted metrics from the gaze data that serve as proxies for underlying perceptual and cognitive capacities. We used these metrics to characterize potential mechanisms of missed IDs: Cursory Comparison and Mislocalization. We find that missed IDs are associated with shorter comparison times, fewer regions visited, and fewer attempted correspondences between the compared images. Latent print comparisons resulting in erroneous exclusions (a subset of missed IDs) are also more likely to have fixations in different regions and less accurate correspondence attempts than those comparisons resulting in identifications. We also use our derived metrics to describe one atypical examiner who made six erroneous identifications, four of which were on comparisons intended to be straightforward exclusions. The present work helps identify the degree to which missed IDs can be explained using eye-gaze behavior, and the extent to which missed IDs depend on cognitive and decision-making factors outside the domain of eye-tracking methodologies. [ABSTRACT FROM AUTHOR]

During fingerprint comparisons, a latent print examiner visually compares two impressions to determine whether or not they originated from the same source. They consider the amount of perceived detail in agreement or disagreement and accumulate evidence toward same source and different sources propositions. This evidence is then mapped to one of three conclusions: Identification, Inconclusive, or Exclusion. A limitation of this 3‐conclusion scale is it can lose information when translating the conclusion from the internal strength‐of‐evidence value to one of only three possible conclusions. An alternative scale with two additional values, support for different sources and support for common sources, has been proposed by the Friction Ridge Subcommittee of OSAC. The expanded scale could lead to more investigative leads but could produce complex trade‐offs in both correct and erroneous identifications. The aim of the present study was to determine the consequences of a shift to expanded conclusion scales in latent print comparisons. Latent print examiners each completed 60 comparisons using one of the two scales, and the resulting data were modeled using signal detection theory to measure whether the expanded scale changed the threshold for an "Identification" conclusion. When using the expanded scale, examiners became more risk‐averse when making "Identification" decisions and tended to transition both the weaker Identification and stronger Inconclusive responses to the "Support for Common Source" statement. The results demonstrate the utility of an expanded conclusion scale and also provide guidance for the adoption of these or similar scales. [ABSTRACT FROM AUTHOR]

Forensic evidence often involves an evaluation of whether two impressions were made by the same source, such as whether a fingerprint from a crime scene has detail in agreement with an impression taken from a suspect. Human experts currently outperform computer-based comparison systems, but the strength of the evidence exemplified by the observed detail in agreement must be evaluated against the possibility that some other individual may have created the crime scene impression. Therefore, the strongest evidence comes from features in agreement that are also not shared with other impressions from other individuals. We characterize the nature of human expertise by applying two extant metrics to the images used in a fingerprint recognition task and use eye gaze data from experts to both tune and validate the models. The Attention via Information Maximization (AIM) model (Bruce & Tsotsos, 2009) quantifies the rarity of regions in the fingerprints to determine diagnosticity for purposes of excluding alternative sources. The CoVar model (Karklin & Lewicki, 2009) captures relationships between low-level features, mimicking properties of the early visual system. Both models produced classification and generalization performance in the 75%-80% range when classifying where experts tend to look. A validation study using regions identified by the AIM model as diagnostic demonstrates that human experts perform better when given regions of high diagnosticity. The computational nature of the metrics may help guard against wrongful convictions, as well as provide a quantitative measure of the strength of evidence in casework. [ABSTRACT FROM AUTHOR]

Age-related temporal-processing declines of rapidly presented sequences may involve contributions of sensory memory. This study investigated recall for rapidly presented auditory (vowel) and visual (letter) sequences presented at six different stimulus onset asynchronies (SOA) that spanned threshold SOAs for sequence identification. Younger, middle-aged, and older adults participated in all tasks. Results were investigated at both equivalent performance levels (i.e., SOA threshold) and at identical physical stimulus values (i.e., SOAs). For four-item sequences, results demonstrated best performance for the first and last items in the auditory sequences, but only the first item for visual sequences. For two-item sequences, adults identified the second vowel or letter significantly better than the first. Overall, when temporal-order performance was equated for each individual by testing at SOA thresholds, recall accuracy for each position across the age groups was highly similar. These results suggest that modality-specific processing declines of older adults primarily determine temporal-order performance for rapid sequences. However, there is some evidence for a second amodal processing decline in older adults related to early sensory memory for final items in a sequence. This selective deficit was observed particularly for longer sequence lengths and was not accounted for by temporal masking. [ABSTRACT FROM AUTHOR]

Acquiring expertise in complex visual tasks is time consuming. To facilitate the efficient training of novices on where to look in these tasks, we propose an attentional highlighting paradigm. Highlighting involves dynamically modulating the saliency of a visual image to guide attention along the fixation path of a domain expert who had previously viewed the same image. In Experiment 1, we trained naive subjects via attentional highlighting on a fingerprint-matching task. Before and after training, we asked subjects to freely inspect images containing pairs of prints and determine whether the prints matched. Fixation sequences were automatically scored for the degree of expertise exhibited using a Bayesian discriminative model of novice and expert gaze behavior. Highlighted training causes gaze behavior to become more expert-like not only on the trained images but also on transfer images, indicating generalization of learning. In Experiment 2, to control for the possibility that the increase in expertise is due to mere exposure, we trained subjects via highlighting of fixation sequences from novices, not experts, and observed no transition toward expertise. In Experiment 3, to determine the specificity of the training effect, we trained subjects with expert fixation sequences from images other than the one being viewed, which preserves coarse-scale statistics of expert gaze but provides no information about fine-grain features. Observing at least a partial transition toward expertise, we obtain only weak evidence that the highlighting procedure facilitates the learning of critical local features. We discuss possible improvements to the highlighting procedure. [ABSTRACT FROM AUTHOR]