Effects of vision and haptics on categorizing common objects

Most research on object recognition and categorization centers on vision. However, these phenomena are likely influenced by the commonly used modality of touch. The present study tested this notion by having participants explore three-dimensional objects using vision and haptics in naming and sorting tasks. Results showed greater difficulty naming (recognizing) and sorting (categorizing) objects haptically. For both conditions, error increased from the concrete attribute of size to the more abstract quality of predation, providing behavioral evidence for shared object representation in vision and haptics.     

Causal attributions of obese men and women in genetic testing: Implications of genetic/biological attributions1

The present study sought to investigate genetic/biological attributions of obesity, their associations with a predisposition to obesity and their crossectional and longitudinal implications for weight regulation in obese individuals presenting for genetic testing and counselling. A total of 421 obese men and women underwent psychological and anthropometric assessment and a mutation screen of the melanocortin-4 receptor gene. At study entry, women revealed more genetic/biological attributions than men on the Revised Illness Perception Questionnaire adapted to obesity (86.2% versus 59.7%). Genetic/biological attributions of obesity were associated in both sexes with a family history of obesity, assessed through Stunkard's Figure Rating Scale. In both sexes, genetic/biological attributions were unrelated to weight regulation beliefs and behaviour (i.e. self-efficacy, controllability beliefs, restrained eating and physical activity), assessed through standardised questionnaires or interview at baseline and at six-month follow-up. In addition, causal attributions and weight regulation beliefs and behaviour were not predictive of body mass index at six-month follow-up. Overall, the results indicate that causal attributions of obesity to genetic/biological factors in obese individuals presenting for genetic screening and counselling are crossectionally and longitudinally unrelated to weight regulation and longer-term weight outcome. Those who attribute their obesity to genetic/biological factors likely have a familial obesity risk.     

Neural substrates for episodic encoding and recognition of unfamiliar faces

Functional MRI was used to investigate brain activation in healthy volunteers during encoding of unfamiliar faces as well as during correct recognition of newly learned faces (CR) compared to correct identification of distractor faces (CF), missed alarms (not recognizing previously presented faces, MA), and false alarms (incorrectly recognizing newly presented faces, FA). Encoding was associated with frontal, occipital/fusiform, thalamic, and cerebellar activation. CR produced activation in frontal and cerebellar regions, whereas CF activated frontal and occipitotemporal regions as well as the thalamus. In contrast, MA was associated with frontal and thalamic activation, and FA with frontal activation. The CR minus CF comparison showed left lateral prefrontal and parietal activation, while no suprathreshold positive signal changes were detected when subtracting the other conditions (CR minus MA, CR minus FA, and vice versa). These results support the view that the successful episodic retrieval of newly learned faces is based on a dorsal visual stream mechanism.     

Self‐esteem discrepancies and defensive reactions to social feedback

Recent research has provided increasing evidence that discrepancies between implicit and explicit self‐esteem (SE) are related to defensiveness. However, only one pattern, called fragile SE (a combination of high explicit and low implicit SE), has been the focus of research so far. Relatively little attention has been paid to the second possible SE discrepancy (low explicit/high implicit). We propose that both types of discrepancies are maladaptive, because they indicate a lack of integration in self‐representation. We conducted two studies on the correlates of discrepant SE in the sphere of defensiveness. We hypothesized that persons with discrepant SE exhibit more defensive behaviour than individuals with congruent SE. In two student samples, explicit SE was measured by means of the Multidimensional Self‐Esteem Scale. Implicit SE was measured with the Name Letter Technique (Study 1) and an Implicit Association Test (Study 2). In Study 1 (N = 102) we examined effects of implicit and explicit SE on defensive reactions to ambiguous statements. For this purpose, we adapted the Ambiguous Statements Task (AST, Tafarodi, 1998 ), a procedure that measures participants' tendency to interpret ambiguous expressions in a positive vs negative manner. We found that the combination of low explicit SE and high implicit SE was associated with a more positive interpretation of the ambiguous statements. Study 2 (N = 87) investigated the effects of discrepant SE on reactions to SE threat in an experimental setting. The time participants spent reading positive or negative social feedback was used as an unobtrusive measure of defensiveness. We found that people with discrepant SE went through the negative feedback faster than people with congruent SE. In sum, the studies provide converging evidence that both kinds of discrepancies between implicit and explicit SE are related to defensive behaviour.     

Gender differences in episodic memory and visual working memory including the effects of age

Analysing the relationship between gender and memory, and examining the effects of age on the overall memory-related functioning, are the ongoing goals of psychological research. The present study examined gender and age group differences in episodic memory with respect to the type of task. In addition, these subgroup differences were also analysed in visual working memory. A sample of 366 women and 330 men, aged between 16 and 69 years of age, participated in the current study. Results indicate that women outperformed men on auditory memory tasks, whereas male adolescents and older male adults showed higher level performances on visual episodic and visual working memory measures. However, the size of gender-linked effects varied somewhat across age groups. Furthermore, results partly support a declining performance on episodic memory and visual working memory measures with increasing age. Although age-related losses in episodic memory could not be explained by a decreasing verbal and visuospatial ability with age, women's advantage in auditory episodic memory could be explained by their advantage in verbal ability. Men's higher level visual episodic memory performance was found to result from their advantage in visuospatial ability. Finally, possible methodological, biological, and cognitive explanations for the current findings are discussed.     

Dopaminergic medication alters auditory distractor processing in Parkinson's disease

Parkinson's disease (PD) patients show signs of cognitive impairment, such as executive dysfunction, working memory problems and attentional disturbances, even in the early stages of the disease. Though motor symptoms of the disease are often successfully addressed by dopaminergic medication, it still remains unclear, how dopaminergic therapy affects cognitive function. The main objective of this study was to assess the effect of dopaminergic medication on visual and auditory attentional processing. 14 PD patients and 13 matched healthy controls performed a three-stimulus auditory and visual oddball task while their EEG was recorded. The patients performed the task twice, once on- and once off-medication. While the results showed no significant differences between PD patients and controls, they did reveal a significant increase in P3 amplitude on- vs. off-medication specific to processing of auditory distractors and no other stimuli. These results indicate significant effect of dopaminergic therapy on processing of distracting auditory stimuli. With a lack of between group differences the effect could reflect either 1) improved recruitment of attentional resources to auditory distractors; 2) reduced ability for cognitive inhibition of auditory distractors; 3) increased response to distractor stimuli resulting in impaired cognitive performance; or 4) hindered ability to discriminate between auditory distractors and targets. Further studies are needed to differentiate between these possibilities.     

Rapid communication: Sex differences in artificial grammar learning: evidence for different strategies in men and women

In this article we report an experiment that investigated differences in classification performance of women and men in artificial grammar learning (AGL). Women's and men's responses correspond to a large extent. Consistent differences, however, were found in a variable that codes overlaps between training and test items in terms of string fragments. The results are best explained by the assumption that women and men apply different cognitive strategies at test.     

Vibrotactile localization on the abdomen: effects of place and space

In this study, we explore the conditions for accurate localization of vibrotactile stimuli presented to the abdomen. Tactile orientation systems intended to provide mobility information for people who are blind depend on accurate identification of location of stimuli on the skin, as do systems designed to indicate target positions in space or the status of remotely operated devices to pilots or engineers. The spatial acuity of the skin has been examined for simple touch, but not for the types of vibrating signals used in such devices. The ability to localize vibratory stimuli was examined at sites around the abdomen and found to be a function of separation among loci and, most significantly, of place on the trunk. Neither the structures underlying the skin nor the types of tactor tested appeared to affect localization. Evidence was found for anatomically defined anchor points that provide localization referents that enhance performance even with wide target spacing.     

Prenatal stress and risk for psychopathology: specific effects or induction of general susceptibility?

This review focuses on prenatal stress as a risk factor for psychopathology. Evidence from animal studies is summarized, and the relevance of prenatal stress models in animals for human studies is discussed. In the offspring of prenatally stressed animals, overactivity and impaired negative feedback regulation of the hypothalamic-pituitary-adrenal axis are consistent findings and may reflect a pathophysiological mechanism involved in the development of psychopathology. Reduced activity of the opioid GABA/benzodiazepine, serotonin, and dopamine systems and increased activity of the sympathico-adrenal system have been found as well. These alterations have been linked to a diverse spectrum of psychopathology. Therefore, the evidence supports the view that exposure to prenatal stress may result in a general susceptibility to psychopathology, rather than exerting a direct effect on a specific form of psychopathology.     

Mood and flexibility in categorization: a conceptual replication

The present study tested the hypothesis that positive mood facilitates cognitive flexibility in categorization, i.e., positive mood enhances the ability to categorize flexibly at broad and narrow levels contingent on task requirement. The study was a conceptual replication of the 1990 work by Murray, Sujan, Hirt, and Sujan. Unlike the original study, it was carried out on the WWW with some modifications in the procedure. Participants were 29 women and 132 men whose average age was 29 yr. They were put into a positive, negative, or neutral mood using the Velten technique. Mood was measured with standard mood scales. Subjects then listed similarities differences between two entertainment TV shows. Contrary to the prediction, participants in a positive mood did not list a higher number, more diverse, or more unusual similarities and differences between the shows, and they were not faster than participants with neutral or negative moods. It is concluded that the influence of mood on cognitive flexibility needs to be reconsidered. In research, temporal aspects of categorization performance as well as a wider range of mood valences should be taken into account.