Conceptual set as a top-down constraint on visual object identification

Four studies are reported which demonstrate that indirectly, loosely related information, otherwise known as conceptual set, modulates object identification. Studies 1A and 1B demonstrate the impact of indirect, nonspecific, non-perceptual, conceptual primes on the interpretation of ambiguous visual figures. Study 2 demonstrates that indirect, conceptual information (category of farm animals) biases identification without requiring the activation of direct perceptual information (here the image of a horse). Study 3 uses a non-linguistic dependent measure to address the alternative explanation that language and not perception mediates the relationship between incidental conceptual prime and biased object identification. These results suggest that conceptual set constrains object identification.     

Stability in young infants' discrimination of optic flow

Although considerable progress has been made in understanding how adults perceive their direction of self-motion, or heading, from optic flow, little is known about how these perceptual processes develop in infants. In 3 experiments, the authors explored how well 3- to 6-month-old infants could discriminate between optic flow patterns that simulated changes in heading direction. The results suggest that (a) prior to the onset of locomotion, the majority of infants discriminate between optic flow displays that simulate only large (> 22 deg.) changes in heading, (b) there is minimal development in sensitivity between 3 and 6 months, and (c) optic flow alone is sufficient for infants to discriminate heading. These data suggest that spatial abilities associated with the dorsal visual stream undergo prolonged postnatal development and may depend on locomotor experience.     

The forest, the trees, and the chameleon: context dependence and mimicry

Three studies examined the relation between context dependence in information processing and behavioral mimicry. In Experiment 1, a field-dependent cognitive style was related to a greater tendency to mimic a target's behavior. In Experiment 2 context dependence was experimentally manipulated, and results showed more mimicry in the session where a context-dependent processing style was induced compared with the session where a context-independent processing style was induced. Experiment 3 provided evidence for bidirectionality in the relation between context dependence and mimicry. Specifically, participants whose posture and behavior had been unobtrusively mimicked by an experimenter subsequently processed information in a more context-dependent manner than did nonmimicked participants. Taken together, these results illustrate the interplay between basic cognitive and behavioral processes.     

The emulation theory of representation: motor control, imagery, and perception

The emulation theory of representation is developed and explored as a framework that can revealingly synthesize a wide variety of representational functions of the brain. The framework is based on constructs from control theory (forward models) and signal processing (Kalman filters). The idea is that in addition to simply engaging with the body and environment, the brain constructs neural circuits that act as models of the body and environment. During overt sensorimotor engagement, these models are driven by efference copies in parallel with the body and environment, in order to provide expectations of the sensory feedback, and to enhance and process sensory information. These models can also be run off-line in order to produce imagery, estimate outcomes of different actions, and evaluate and develop motor plans. The framework is initially developed within the context of motor control, where it has been shown that inner models running in parallel with the body can reduce the effects of feedback delay problems. The same mechanisms can account for motor imagery as the off-line driving of the emulator via efference copies. The framework is extended to account for visual imagery as the off-line driving of an emulator of the motor-visual loop. I also show how such systems can provide for amodal spatial imagery. Perception, including visual perception, results from such models being used to form expectations of, and to interpret, sensory input. I close by briefly outlining other cognitive functions that might also be synthesized within this framework, including reasoning, theory of mind phenomena, and language.     

Inhibitory control in Obsessive-Compulsive Disorder

The clinical features of Obsessive-Compulsive Disorder (OCD) suggest that a fundamental deficit of inhibitory control is intrinsic to the disorder. In this preliminary study, we sought to examine cognitive disinhibition in OCD by using an established laboratory technique. The stop signal task was administered to a higher functioning, untreated group of individuals with OCD, and to healthy comparison participants. Surprisingly, the OCD participants exhibited more accurate performance, suggesting better inhibitory control on this task. This unexpected finding suggests that higher functioning individuals with OCD are capable of adequate inhibition in certain contexts. It was speculated, however, that emotional stimulation might negatively affect performance and that this might be studied in subsequent research.     

Habituation assessment in infancy

Infant-control habituation methodology, although serving the research community well, has never been carefully analyzed. A main use is to equate infants in their level of habituation prior to experimental manipulations in a posthabituation phase. When studied analytically and with simulation, it is found to have serious difficulties. It inadvertently recruits infants with large variations in performance while discriminating against those with less variable performance. For nonhabituating infants, its Type I error rates can approach 1. A model-based nonlinear regression framework is proposed, which, because of large individual differences in infants, takes as the unit of analysis the individual infant. It is shown to be more powerful and efficient than existing procedures and can offer practical and theoretical benefits.     

Work organization, economic inequality, and depression among nursing assistants: a multilevel modeling approach

To investigate the relationships among the nursing home work environment, emotional strain, and depression in Nursing Assistants in Ohio and West Virginia, this cross-sectional study was conducted with 395 Nurse Assistants in 49 nursing homes in Ohio and West Virginia. Organizational attributes were measured independently at the individual and organizational levels. Multilevel modeling techniques were used to analyze the data. Our methods examined nursing home organizational structure (ownership type, managerial style), and work organization (emotional strain) was examined in relation to the prevalence of depression among nursing assistants. Our findings suggest workplace emotional strain and age are associated with increased odds of depression. Implications of our work include that work in nursing homes for the environment it fosters has a strong effect on emotional strain and depression among Nursing Assistants.     

Attention Deficit-Hyperactivity Disorder, Depression, and Self- and Other-Assessments of Social Competence: A Developmental Study

This study examined whether others (i.e., teachers and parents) and self-appraisals of social competence mediated the relationship between Attention-Deficit/Hyperactivity Disorder (ADHD) and depression. To determine whether age moderated the effects of the mediation, the total sample was divided into younger (under 9) and older (at or above 9 years) age levels. The total sample (age range 6.6 to 11.7 years) was primarily male (194 boys and 52 females) and consisted of 148 children diagnosed with ADHD and 98 community controls. Three central findings were derived from this study. First, there was a strong relationship between ADHD (with and without comorbid ODD/CD) and depression in both younger and older aged children. Among younger children with ADHD, there was no differential influence on the level of depression depending on whether or not ADHD was comorbid with ODD/CD; in contrast, with older children, comorbid ODD/CD had higher levels of depression than was the case for children with ADHD that did not display such comorbidity. Second, with younger children approximately half of the relationship between ADHD (with and without comorbid ODD/CD) and depression was exclusively mediated by others appraisal of social competence. Third, a more complex relationship between ADHD and depression emerged during the later part of the childhood years. As such, the relationship between ADHD, others appraisals of social competence, and depression was further mediated by self-appraisals of social competence. Findings are discussed in terms of developmental theory and theoretical models of childhood depression.Rick Ostrander and David S. Crystal contributed equally to this article, and the order of authorship was determined by a coin toss.     

Linking automatic evaluation to mood and information processing style: consequences for experienced affect, impression formation, and stereotyping

According to the feelings-as-information account, a person's mood state signals to him or her the valence of the current environment (N. Schwarz & G. Clore, 1983). However, the ways in which the environment automatically influences mood in the first place remain to be explored. The authors propose that one mechanism by which the environment influences affect is automatic evaluation, the nonconscious evaluation of environmental stimuli as good or bad. A first experiment demonstrated that repeated brief exposure to positive or negative stimuli (which leads to automatic evaluation) induces a corresponding mood in participants. In 3 additional studies, the authors showed that automatic evaluation affects information processing style. Experiment 4 showed that participants' mood mediates the effect of valenced brief primes on information processing.     

Frames of reference for anticipatory action in 4-month-old infants

The spatial representations of 4-month-old infants were examined in two experiments using a modified version of the visual expectation paradigm (VExP). The experiments were designed in order to determine what spatial frames of reference were available to infants for making anticipatory saccades. In Experiment 1, we found that infants most often used a retinocentric frame of reference that did not take into account their current eye position in making an anticipatory saccade. However, Experiment 2 revealed that under certain conditions infants are more likely to make anticipatory saccades consistent with a body- or object-centred frame of reference. The main difference between the two experiments was the degree to which the featural properties of the stimuli varied. The results shed light on the development of spatial representations for action in infancy.