The role of higher level adaptive coding mechanisms in the development of face recognition

Developmental improvements in face identity recognition ability are widely documented, but the source of children’s immaturity in face recognition remains unclear. Differences in the way in which children and adults visually represent faces might underlie immaturities in face recognition. Recent evidence of a face identity aftereffect (FIAE), in which adaptation (exposure) to a particular identity causes a previously neutral face to take on the computationally opposite identity, suggests that adults code faces in an opponent fashion relative to an average face. One previous study showed comparable FIAEs in 8-year-olds and adults but did not demonstrate that adaptation was selective for high-level representations in both groups. Using a developmentally appropriate FIAE task, we investigated whether children show adult-like adaptation for facial identity when adapting and test images differ in size. Both age groups showed an equivalent FIAE, suggesting that qualitative changes in the use of higher level adaptive coding mechanisms do not drive the developmental improvements in face recognition ability, at least from 8 years of age.     

Independent benefits of contact and friendship on attitudes toward homosexuals among authoritarians and highly identified heterosexuals

Although intergroup contact is generally associated with positive intergroup attitudes, little is known about whether individual differences moderate these relations, or how contact might operate among prejudice‐prone individuals. The present investigation explores Person × Contact and Person × Friendship interaction patterns among heterosexual university students. As expected, the positive relations of right‐wing authoritarianism (RWA) and heterosexual identification with prejudice against homosexuals were weakened when participants reported increased contact, more positive contact, direct (personal) friendships, or indirect friendships (i.e., ingroup friends with outgroup friends) with homosexuals. These patterns held after controlling statistically for each person or situation variable. Contact and friendship exerted smaller or negligible effects among low authoritarians or low identifiers. Tests of indirect effects revealed that among high authoritarians or high identifiers, contact and friendship exerted influence on attitudes through group‐level perceptions that homosexuals promote societal values and through increased self–other overlap with gay friends, each otherwise resisted by these individuals. Overall these results suggest that: (a) intergroup contact and intergroup friendship are related but distinct constructs; and (b) past findings underestimate contact effects by collapsing across levels of personal biases. Copyright © 2008 John Wiley & Sons, Ltd.     

Plasma BDNF is reduced among middle-aged and elderly women with impaired insulin function: Evidence of a compensatory mechanism

Brain-derived neurotrophic factor (BDNF) plays a regulatory role in neuronal differentiation and synaptic plasticity and has been linked to glucose regulation and cognition. Associations among plasma BDNF, cognition, and insulin function were explored. Forty-one participants with impaired insulin function (IIF), ranging from insulin resistance to type 2 diabetes mellitus (T2DM), were matched with 41 healthy controls on gender, age, education, and IQ. Participants received complete medical, neurological, psychiatric, and neuropsychological evaluations. IIF individuals had significantly lower plasma BDNF levels than controls, particularly females, and higher BDNF levels were associated with poorer explicit memory in IIF females, suggesting that higher levels within this group may reflect the body’s efforts to respond to damage. After accounting for age, education, and HbA1c, BDNF significantly predicted 13.1–23.5% of the variance in explicit memory in IIF women. These findings suggest that BDNF elevations within diseased groups may not always be a marker of health.     

A new argument for skepticism

The traditional argument for skepticism relies on a comparison between a normal subject and a subject in a skeptical scenario: because there is no relevant difference between them, neither has knowledge. Externalists respond by arguing that there is in fact a relevant difference—the normal subject is properly situated in her environment. I argue, however, that there is another sort of comparison available—one between a normal subject and a subject with a belief that is accidentally true—that makes possible a new argument for skepticism. Unlike the traditional form of skeptical argument, this new argument applies equally well to both internalist and externalist theories of knowledge.

Knowledge about a common source can promote visual- haptic integration

The brain integrates object information from multiple sensory systems to form a unique representation of our environment. Temporal synchrony and spatial coincidence are important factors for multisensory integration, indicating that the multisensory signals come from a common source. Spatial separations can lead to a decline of visual-haptic integration (Gepshtein et al, 2005 Journal of Vision 5 1013-1023). Here we tested whether prior knowledge that two signals arise from the same object can promote integration even when the signals are spatially discrepant. In one condition, participants had direct view of the object they touched. In a second condition, mirrors were used to create a spatial separation between the seen and the felt object. Participants saw the mirror and their hand in the mirror exploring the object and thus knew that they were seeing and touching the same object. To determine the visual-haptic interaction we created a conflict between the seen and the felt shape using an optically distorting lens that made a rectangle look like a square. Participants judged the shape of the probe by selecting a comparison object matching in shape. We found a mutual biasing effect of shape information from vision and touch, independent of whether participants directly looked at the object they touched or whether the seen and the felt object information was spatially separated with the aid of a mirror. This finding suggests that prior knowledge about object identity can promote integration, even when information from vision and touch is provided at spatially discrepant locations.     

Treatment integrity of school-based interventions with children in the journal of applied behavior analysis 1991-2005

We reviewed all school-based experimental studies with individuals 0 to 18 years published in the Journal of Applied Behavior Analysis (JABA) between 1991 and 2005. A total of 142 articles (152 studies) that met review criteria were included. Nearly all (95%) of these experiments provided an operational definition of the independent variable, but only 30% of the studies provided treatment integrity data. Nearly half of studies (45%) were judged to be at high risk for treatment inaccuracies. Treatment integrity data were more likely to be included in studies that used teachers, multiple treatment agents, or both. Although there was a substantial increase in reporting operational definitions of independent variables, results suggest that there was only a modest improvement in reported integrity over the past 30 years of JABA studies. Recommendations for research and practice are discussed.     

The interaction of pathways to fear in childhood anxiety: a preliminary study

Recent research has shown that the verbal information pathway to fear creates long-term fear cognitions and can create cognitive biases and avoidance in children. However, the interaction between the verbal information pathway to fear and other pathways is untested. This experiment exposed children (aged 6–8) to threat information about a novel animal to see the impact on a measure of avoidance after a subsequent simulated direct negative encounter with that animal. Results showed that a direct negative experience (without prior information) or threat information (without a subsequent negative experience) produced similar effects, but in combination (verbal threat information followed by a direct negative experience) the effect was significantly magnified. These results support theories of fear acquisition that suppose that verbal information impacts on the strength of associations formed in subsequent conditioning episodes, and suggest that pathways to fear have interactive effects.     

Workplace emotions: the role of supervision and leadership

In this experience sampling study, the authors examined the role of organizational leaders in employees' emotional experiences. Data were collected from health care workers 4 times a day for 2 weeks. Results indicate supervisors were associated with employee emotions in 3 ways: (a) Employees experienced fewer positive emotions when interacting with their supervisors as compared with interactions with coworkers and customers; (b) employees with supervisors high on transformational leadership experienced more positive emotions throughout the workday, including interactions with coworkers and customers; and (c) employees who regulated their emotions experienced decreased job satisfaction and increased stress, but those with supervisors high on transformational leadership were less likely to experience decreased job satisfaction. The results also suggest that the effects of emotional regulation on stress are long lasting (up to 2 hr) and not easily reduced by leadership behaviors.     

Age trends in stimulus overselectivity

Stimulus overselectivity refers to the phenomenon whereby stimulus control over behavior is exerted only by a limited subset of the total number of stimuli present during discrimination learning. It often is displayed by individuals with autistic spectrum disorders or learning disabilities, but is not exclusive to those groups. The present studies investigated the impact of aging on stimulus control and overselectivity. Three age groups--18-22, 47-55, and 70-80 year olds-were studied in two experiments. All participants were trained on a simple discrimination task, randomly assigned to one of two conditions (either with or without a distractor task), and then tested for the emergence of overselectivity (Experiment 1). In Experiment 2 responding controlled by the overselected stimulus elements was reduced by introducing a verbal punisher. In subsequent tests, control of behavior by the previously underselected elements from Experiment 1 was enhanced across the two younger age groups but not the oldest group of participants. The results are discussed in relation to the attention-deficit and overshadowing accounts of overselectivity.     

Human sensitivity to reinforcement feedback functions

Two experiments investigated human sensitivity to the temporally extended aspects of reinforcement schedules. Experiment 1 investigated human sensitivity to the extended and local aspects of three reinforcement schedules: variable ratio (VR), variable interval (VI), and variable-interval-plus-linear-feedback (VI+) schedules. Experiment 2 investigated this sensitivity on two reinforcement schedules: VI and VI+ schedules. In both experiments, there was evidence of sensitivity to the temporally extended aspects of the schedule: There were differences between the response rate on the VI+ and yoked-VI schedules, but no statistical difference in rates of response between the VR and VI+ schedules. The VI+ versus VI difference was much more pronounced when a lower response force needed to depress a lever was used. These results suggest that human subjects do show some sensitivity to temporally extended aspects of schedules of reinforcement.