Gaze following: why (not) learn it?

We propose a computational model of the emergence of gaze following skills in infant-caregiver interactions. The model is based on the idea that infants learn that monitoring their caregiver's direction of gaze allows them to predict the locations of interesting objects or events in their environment (Moore & Corkum, 1994). Elaborating on this theory, we demonstrate that a specific Basic Set of structures and mechanisms is sufficient for gaze following to emerge. This Basic Set includes the infant's perceptual skills and preferences, habituation and reward-driven learning, and a structured social environment featuring a caregiver who tends to look at things the infant will find interesting. We review evidence that all elements of the Basic Set are established well before the relevant gaze following skills emerge. We evaluate the model in a series of simulations and show that it can account for typical development. We also demonstrate that plausible alterations of model parameters, motivated by findings on two different developmental disorders - autism and Williams syndrome - produce delays or deficits in the emergence of gaze following. The model makes a number of testable predictions. In addition, it opens a new perspective for theorizing about cross-species differences in gaze following.     

Adaptation-level theory, opponent process theory, and dispositions: an integrated approach to the stability of job satisfaction

Research suggests that the stability of job satisfaction is partially the result of dispositions (J. J. Connolly & C. Viswesvaran, 2000; C. Dormann & D. Zapf, 2001; T. A. Judge & J. E. Bono, 2001a; T. A. Judge, D. Heller, & M. K. Mount, 2002). Opponent process theory (R. L. Solomon & J. D. Corbit, 1973, 1974) and adaptation-level theory (H. Helson, 1948) are alternative explanations of this stability that explain how environmental effects on job satisfaction dissipate across time. On the basis of an integration of these explanations, the authors propose that dispositions (a) influence employees' equilibrium or adaptation level of job satisfaction, (b) influence employees' sensitivity to workplace events, and (c) influence the speed at which job satisfaction returns to equilibrium after one is exposed to a workplace event. Research and applied implications are discussed.     

Prefrontal and hippocampal contributions to visual associative recognition: interactions between cognitive control and episodic retrieval

The ability to recover episodic associations is thought to depend on medial-temporal lobe mnemonic mechanisms and frontal lobe cognitive control processes. The present study examined the neural circuitry underlying non-verbal associative retrieval, and considered the consequences of successful retrieval on cognitive control demands. Event-related fMRI data were acquired while subjects retrieved strongly or weakly associated pairs of novel visual patterns in a two-alternative forced choice associative recognition paradigm. Behaviorally, successful retrieval of strongly associated relative to weakly associated pairs was more likely to be accompanied by conscious recollection of the pair's prior co-occurrence. At the neural level, right ventrolateral prefrontal cortex (VLPFC) and hippocampus were more active during successful retrieval of Strong than of Weak associations, consistent with a role in visual associative recollection. By contrast, Weak trials elicited greater activation in right anterior cingulate cortex (ACC), which may detect conflict between the similarly familiar target and foil stimuli in the absence of recollection. Consistent with this interpretation, stronger ACC activity was associated with weaker hippocampal and stronger right dorsolateral PFC (DLPFC) responses. Thus, recollection of relevant visual associations (hippocampus and VLPFC) results in lower levels of mnemonic conflict (ACC) and decreased familiarity-based monitoring demands (DLPFC). These findings highlight the interplay between cognitive control and episodic retrieval.     

Is perception discrete or continuous?

How does conscious perception evolve following stimulus presentation? The idea that perception relies on discrete processing epochs has been often considered, but never widely accepted. The alternative, a continuous translation of the external world into explicit perception, although more intuitive and subjectively appealing, cannot satisfactorily account for a large body of psychophysical data. Cortical and thalamocortical oscillations in different frequency bands could provide a neuronal basis for such discrete processes, but are rarely analyzed in this context. This article reconciles the unduly abandoned topic of discrete perception with current views and advances in neuroscience.     

How owls structure visual information

Recent studies on perceptual organization in humans claim that the ability to represent a visual scene as a set of coherent surfaces is of central importance for visual cognition. We examined whether this surface representation hypothesis generalizes to a non-mammalian species, the barn owl (Tyto alba). Discrimination transfer combined with random-dot stimuli provided the appropriate means for a series of two behavioural experiments with the specific aims of (1) obtaining psychophysical measurements of figure–ground segmentation in the owl, and (2) determining the nature of the information involved. In experiment 1, two owls were trained to indicate the presence or absence of a central planar surface (figure) among a larger region of random dots (ground) based on differences in texture. Without additional training, the owls could make the same discrimination when figure and ground had reversed luminance, or were camouflaged by the use of uniformly textured random-dot stereograms. In the latter case, the figure stands out in depth from the ground when positional differences of the figure in two retinal images are combined (binocular disparity). In experiment 2, two new owls were trained to distinguish three-dimensional objects from holes using random-dot kinematograms. These birds could make the same discrimination when information on surface segmentation was unexpectedly switched from relative motion to half-occlusion. In the latter case, stereograms were used that provide the impression of stratified surfaces to humans by giving unpairable image features to the eyes. The ability to use image features such as texture, binocular disparity, relative motion, and half-occlusion interchangeably to determine figure–ground relationships suggests that in owls, as in humans, the structuring of the visual scene critically depends on how indirect image information (depth order, occlusion contours) is allocated between different surfaces. Electronic Publication     

Preliminary examination of sex differences in depressive symptoms among adolescent psychiatric inpatients: the role of anxious symptoms and generalized negative affect.

Assessed the emerging view that generalized negative affect and anxious symptoms are important in understanding sex differences in depressive symptoms. Sixty-three adolescent psychiatric inpatients (32 boys, 31 girls), ages 12 to 16 (M = 13.87, SD = 1.36), completed measures of positive and negative affect and anxious and depressive symptoms. Results demonstrated, as predicted, that depressive and anxious symptoms were more highly associated in adolescent girls than boys. Furthermore, girls with depressive symptoms were more likely to have comorbid anxious symptoms than boys with depressive symptoms. Sex differences were not found for adolescents with specific depressive symptoms and specific anxious symptoms (i.e., the absence of comorbidity). Our findings supported the possibility that sex differences in pure forms of depression are overestimated and that comorbid internalizing conditions may be more prevalent in adolescent girls than boys.     

Misadventures In Conditional Expectation: The Two-Envelope Problem

Several fallacies of conditionalization are illustrated, using the two-envelope problem as a case in point This revised version was published online in July 2006 with corrections to the Cover Date.     

Facial expression recognition ability among women with borderline personality disorder: implications for emotion regulation?

This study examined recognition of facial expressions of emotion among women diagnosed with borderline personality disorder (BPD; n = 21), compared to a group of women with histories of childhood sexual abuse with no current or prior diagnosis of BPD (n = 21) and a group of women with no history of sexual abuse or BPD (n = 20). Facial recognition was assessed by a slide set developed by Ekman and Matsumoto (Japanese and Caucasian Facial Expressions of Emotion and Neutral Faces, 1992), expanded and improved from previous slide sets, and utilized a coding system that allowed for free responses rather than the more typical fixed-response format. Results indicated that borderline individuals were primarily accurate perceivers of others' emotions and showed a tendency toward heightened sensitivity on recognition of fear, specifically. Results are discussed in terms of emotional appraisal ability and emotion dysregulation among individuals with BPD.