Using cognitive models to map relations between neuropsychological disorders and human decision-making deficits

Findings from a complex decision-making task (the Iowa gambling task) show that individuals with neuropsychological disorders are characterized by decision-making deficits that lead to maladaptive risk-taking behavior. This article describes a cognitive model that distills performance in this task into three different underlying psychological components: the relative impact of rewards and punishments on evaluations of options, the rate that the contingent payoffs are learned, and the consistency between learning and responding. Findings from 10 studies are organized by distilling the observed decision deficits into the three basic components and locating the neuropsychological disorders in this component space. The results reveal a cluster of populations characterized by making risky choices despite high attention to losses, perhaps because of difficulties in creating emotive representations. These findings demonstrate the potential contribution of cognitive models in building bridges between neuroscience and behavior.     

ROCs in recognition with and without identification

Receiver operating characteristics (ROCs) for the recognition of unidentified word fragments were analysed and compared with ROCs for the recognition of identified word fragments. In all conditions reported here, the z-transformed ROCs (z-ROCs) for recognition without identification were linear, with slopes near 1.0. In contrast, the z-ROCs for recognition with identification each had both a linear and a quadratic component, and a slope of substantially less than 1.0. Because the recognition of unidentified word fragments likely results from a familiarity process, the present study examined how well the effect can be explained by global matching variants of signal detection theory. Global matching models predict that memory should be better for strong items from a mixed list than for strong items from a pure list, and should be worse for weak items from a mixed list than for weak items from a pure list; however, only the latter pattern was shown for the recognition of unidentified items.     

Focused attention is not enough to activate discontinuities in lines, but scrutiny is

We distinguish between the roles played by spatial attention and conscious intention in terms of their impact on the processing of segmentation signals, like discontinuities in lines, associated with the act of scrutinizing. We showed previously that the processing of discontinuities in lines can be activated. This is evidenced by an impairment in the detection of a gap between parallel elements when it follows a gap between collinear elements in the same location and orientation. This effect is no longer observed if attention is divided between two gaps in the first stimulus. The results from this study show that focusing attention on a gap between collinear elements is not enough to observe a modulation, consistently with the need to integrate, rather than to separate, collinear elements in usual conditions. The modulation is sensitive to the conscious expectations of subjects, suggesting that an intention can trigger modulations that spatial attention cannot.     

Bodies and their parts

How do we think about the space of bodies? Several accounts of mental representations of bodies were addressed in body part verification tasks. Animagery account predicts shorter times to larger parts (e.g., back < hand). Apart distinctiveness account predicts shorter times to more discontinuous parts (e.g., arm < chest). Apart significance account predicts shorter times to parts that are perceptually distinct and functionally important (e.g., head < back). Because distinctiveness and significance are correlated, the latter two accounts are difficult to distinguish. Both name-body and body-body comparisons were investigated in four experiments. In all, larger parts were verified more slowly than smaller ones, eliminating the imagery/size account. Despite the correlation between distinctiveness and significance, the data suggest that when comparisons are perceptual (body-body), part distinctiveness is the best predictor, and when explicit or implicit naming is involved, part significance is the best predictor. Naming seems to activate the functional aspects of bodies.     

What perceptual rules do capuchin monkeys (Cebus apella) follow in completing partly occluded figures?

Capuchin monkeys (Cebus apella) matched a variety of rodlike figures, distinguishable only by their central portions. The monkeys were then tested for perceptual completion rules by examining which comparison figures they would choose as matching the sample with the critical central portion occluded by a horizontal belt. In Experiment 1, the monkeys overwhelmingly chose a straight rod over disconnected rods and rods having irregular shapes at their center, irrespective of the presence-absence of common motion of visible parts of the samples. The monkeys chose a connected rod for relatable rods and disconnected rods for non-relatable ones in Experiment 2. In Experiments 3 and 4, some of the monkeys chose rods specified by the global regularity of the contour, whereas others did not. Experiment 5 showed that humans and capuchin monkeys basically follow similar perceptual rules in completing occluded contours, but the global regularity rule may be stronger in humans.     

Recognition by humans and pigeons of novel views of 3-D objects and their photographs

Humans and pigeons were trained to discriminate between 2 views of actual 3-D objects or their photographs. They were tested on novel views that were either within the closest rotational distance between the training views (interpolated) or outside of that range (extrapolated). When training views were 60 degrees apart, pigeons, but not humans, recognized novel views of actual objects better than their pictures. Further, both species recognized interpolated views of both stimulus types better than extrapolated views, but a single distinctive geon enhanced recognition of novel views only for humans. When training views were 90 degrees apart, pigeons recognized interpolated views better than extrapolated views with actual objects but not with photographs. Thus, pigeons may represent actual objects differently than their pictures.     

Adults with dyslexia demonstrate space-based and object-based covert attention deficits: shifting attention to the periphery and shifting attention between objects in the left visual field

Performance on a covert visual attention task is compared between a group of adults with developmental dyslexia (specifically phonological difficulties) and a group of age and IQ matched controls. The group with dyslexia were generally slower to detect validly-cued targets. Costs of shifting attention toward the periphery when the target was invalidly cued were significantly higher for the group with dyslexia, while costs associated with shifts toward the fovea tended to be lower. Higher costs were also shown by the group with dyslexia for up-down shifts of attention in the periphery. A visual field processing difference was found, in that the group with dyslexia showed higher costs associated with shifting attention between objects in they LVF. These findings indicate that these adults with dyslexia have difficulty in both the space-based and the object-based components of covert visual attention, and more specifically to stimuli located in the periphery.     

The Beck Anxiety Inventory in Older Adults With Generalized Anxiety Disorder

The authors investigated the psychometric properties of the Beck Anxiety Inventory (BAI) in a sample of 75 older generalized anxiety disorder (GAD) patients and a comparison group of 32 older adults without significant psychopathology. Internal consistency was above .80, and the BAI showed evidence of convergent validity in both groups. Evidence for discriminant validity with respect to measures of depression was weaker. Two items, fearing the worst and nervousness, correctly distinguished 86.5% of patients with GAD and 93.8% of the normal controls. Medical comorbidity was associated with somatic but not cognitive anxiety symptoms in the normal older sample. Overall, results indicate the limitations of the BAI in assessing anxiety symptoms in older adults and suggest the need for use of an instrument focusing on cognitive aspects of anxiety.     

Racial Differences in Responses to the Caregiver Strain Questionnaire

The aim of this study was to examine differences in responses to the Caregiver Strain Questionnaire (CGSQ) between African American and White caregivers of children with emotional and behavioral challenges. Significant item- and scale-level differences were detected across groups with African Americans consistently reporting less strain. We examined whether these differences were more likely due to nonequivalent measurement than to real differences in the experience of caregiver strain. Confirmatory factor analysis showed that the model fit the data well for both racial groups, but there were some differences in structural components. Internal consistency was equivalent across the groups. In an examination of criterion validity, regression analyses showed that African American caregivers experienced a slower rate of increase in objective caregiver strain at a given increase in child internalizing problems. No other race differences were found in the regression analyses. In general, we conclude that the CGSQ can be useful for detecting caregiver strain and identifying family support needs for both White and African American caregivers. Differences across groups in reports of caregiver strain, however, call for more research on racial differences in the impact on the family of caring for a child with emotional and behavioral disorders.     

Sensitivity to social contingencies between 1 and 3 months of age

Infants' sensitivity to social contingencies was assessed. In Study 1, 1-month-old infants and their mothers interacted face-to-face in three types of imperfect contingent interactions: Normal, Non-Contingent and Imitation. One-month-old infants did not discriminate these conditions. In Study 2, 3-month-old infants were tested as in Study 1. At 3 months of age, infants gazed reliably longer in the Imitation condition and smiled reliably more in the Normal than in the Non-Contingent and Imitation interactions. These findings suggest a developmental transition in the sensitivity to social contingencies between 1 and 3 months of age. The relationship between the developing sensitivity to social contingencies and social cognition is discussed.