Near, yet so far: the effect of pictorial cues on spatial attention

Distinct cognitive and neural mechanisms underlie perception and action in near (within-reach) and far (outside-reach) space. Objects in far space can be brought into the brain's near-space through tool-use. We determined whether a near object can be pushed into far space by changing the pictorial context in which it occurs. Participants (n = 372) made relative length judgements for lines presented in near space, but superimposed over photographs of near and far objects. The left segment of the line was overestimated in the baseline and near-context conditions whereas the right was overestimated in the far-context. The change from leftward to rightward overestimation is the same when lines are physically shifted from near to far space. Because participants did not have to do anything in relation to the photograph, the results suggest that simply viewing images with a near/far context can cause a shift of attention along the distal/proximal axis, which may reflect differential activation of the ventral/dorsal visual streams.     

The flexibility of emotional attention: Accessible social identities guide rapid attentional orienting

There is extensive evidence that emotional-especially threatening-stimuli rapidly capture attention. These findings are often explained in terms of a hard-wired and relatively inflexible fear module. We propose an alternative, more flexible mechanism, arguing that motivational relevance is the crucial factor driving rapid attentional orienting. To test our hypothesis, we endowed initially neutral face stimuli with relevance by randomly assigning them to a social in-group or out-group during a 1-min learning phase, and used these faces as cues in a dot probe task to measure rapid attentional orienting. Across three experiments, we observed attentional orienting toward faces assigned to the out-group. Initial rapid orienting (after 100ms, Experiments 1 and 2) was observed only for familiar faces for which group membership was explicitly encoded, suggesting that rapid orienting may be based on affectively charged memory traces. At a later time point (after 500ms, Experiment 3), attention was deployed toward unfamiliar faces sharing a physical attribute (background color) with the familiar out-group faces, suggesting a more time-consuming on-line appraisal of the stimulus. The amount of attentional bias to out-group faces was correlated with individual differences in the accessibility of group identification. Our findings demonstrate that attentional prioritization mechanisms can be flexibly tuned by a brief learning phase of social identity. This is consistent with the idea that attention mechanisms subserving the selection and prioritization of emotional aspects of the environment are not static and hard-wired, but may rapidly adapt to recent changes in motivational contingencies.     

Alcohol affects goal commitment by explicitly and implicitly induced myopia

Alcohol commits people to personally important goals even if expectations of reaching the goals are low. To illuminate this effect, we used alcohol myopia theory, stating that alcohol intoxicated people disproportionally attend to the most salient aspects of a situation and ignore peripheral aspects. When low expectations of reaching an important goal were activated students who consumed alcohol were less committed than students who consumed a placebo. We observed less commitment regardless of whether low expectations were explicitly activated in a questionnaire (Study 1) or implicitly activated through subliminal priming (Study 2). The results imply that, intoxicated people commit to goals according to what aspects of a goal are activated either explicitly or implicitly.     

Integration of hand and finger location in external spatial coordinates for tactile localization

Tactile stimulus location is automatically transformed from somatotopic into external spatial coordinates, rendering information about the location of touch in three-dimensional space. This process is referred to as tactile remapping. Whereas remapping seems to occur automatically for the hands and feet, the fingers may constitute an exception in that some studies have implied purely somatotopic coding of touch to the fingers. When participants judge the order of two tactile stimuli, they often err when the stimulated body parts (usually the two hands) are crossed, presumably because somatotopic and external coordinates are in conflict in crossed postures. Using this task, we investigated, first, whether the fingers are unlike other limbs with regard to spatial coding, by testing whether crossing effects, indicative of external coding, were observable when stimulating two fingers, either on the same or on different hands. Second, we investigated the interaction of hand and finger posture in tactile localization of finger stimuli. Crossing effects emerged when fingers and hands were crossed, suggesting external coding for all body parts. Crossing effects were larger when both hand and finger were located in the hemifield opposite to their body side, and smaller when only hand or finger lay in the opposite hemifield. We suggest that tactile location is estimated by integrating the external location of all relevant body parts, here of a finger and its belonging hand, and that such integrative coding may represent a general principle for body part processing as well as for tool use.     

Introducing a novel method to assess cumulative steroid concentrations: increased hair cortisol concentrations over 6 months in medicated patients with depression

Depression has been linked to increased cortisol concentrations using point measures taken from urine, blood, or saliva samples. However, with regard to hypercortisolism-induced consequences, long-term cumulative cortisol burden is of relevance. Our objective was to use hair analysis as a new method to assess cortisol exposure over 6 months in depressed patients and healthy controls. We examined 23 depressed patients (8 men and 15 women, mean age: 41.6 years (?±?standard deviation (SD), 13.1 years); mean duration of current depressive episode 9 months (?±?SD, 13 months)) and 64 healthy controls, matched for age and gender. Cortisol concentrations in two 3-cm hair segments from near to the scalp were analyzed, representing cortisol secretion during the 6 months prior to sampling. Compared with healthy individuals, depressed patients had higher hair cortisol concentrations in the first (mean?±?SD: 26.7?±?20.8 vs. 18.7?±?11.5?pg/mg, p?相似文献   

Neural correlates of perceptual narrowing in cross‐species face‐voice matching

Integrating the multisensory features of talking faces is critical to learning and extracting coherent meaning from social signals. While we know much about the development of these capacities at the behavioral level, we know very little about the underlying neural processes. One prominent behavioral milestone of these capacities is the perceptual narrowing of face–voice matching, whereby young infants match faces and voices across species, but older infants do not. In the present study, we provide neurophysiological evidence for developmental decline in cross‐species face–voice matching. We measured event‐related brain potentials (ERPs) while 4‐ and 8‐month‐old infants watched and listened to congruent and incongruent audio‐visual presentations of monkey vocalizations and humans mimicking monkey vocalizations. The ERP results indicated that younger infants distinguished between the congruent and the incongruent faces and voices regardless of species, whereas in older infants, the sensitivity to multisensory congruency was limited to the human face and voice. Furthermore, with development, visual and frontal brain processes and their functional connectivity became more sensitive to the congruence of human faces and voices relative to monkey faces and voices. Our data show the neural correlates of perceptual narrowing in face–voice matching and support the notion that postnatal experience with species identity is associated with neural changes in multisensory processing ( Lewkowicz & Ghazanfar, 2009 ).     

The unresponsive bystander: are bystanders more responsive in dangerous emergencies?

Previous research in bystander intervention found that the presence of other bystanders reduces helping behaviour in an emergency (bystander effect). This research was mainly conducted in the context of non‐dangerous, non‐violent emergencies. We hypothesize that the classic bystander effect does not occur in more dangerous situations because: a) they are faster and more clearly recognized as emergency situations; and b) higher costs for refusing help increase the accepted costs for helping. Following this line of reasoning, the present research tests whether the bystander effect is affected by the degree of the emergency's potential danger. Results supported our expectations: In situations with low potential danger, more help was given in the solitary condition than in the bystander condition. However, in situations with high potential danger, participants confronted with an emergency alone or in the presence of another bystander were similarly likely to help the victim. Copyright © 2005 John Wiley & Sons, Ltd.     

Physical,verbal, and relational forms of bullying among German students: age trends,gender differences,and correlates

A revised version of the Bully/Victim Questionnaire [Olweus, 1991] was given to 2,086 fifth–tenth grader students from schools in two German federal states. The results were analysed in terms of frequencies of self‐reports of different forms of bullying (physical, verbal, relational/indirect; for bullies and for victims), gender and grade differences. Overall, 12.1% of the students reported bullying others and 11.1% reported being bullied (victimisation). We classified 2.3% of the students as bully/victims due to their self‐report. Significantly more boys reported bullying others, regardless of bullying form, and significantly more boys than girls were classified as bully/victims. Although there was no gender difference for victimisation at all, boys reported significantly more often than girls being bullied physically. Besides, self‐reports of pure and overlapping forms of bullying behaviour (relational, verbal, physical) were analysed. With regard to age trends, students from middle grades reported the highest rates of bullying. Self‐reported rates of victimisation were higher for younger students, regardless of form of victimisation. Furthermore, class size was not linked to reports of bullying and victimisation. Results from logistic regression analyses emphasised that the variables “gender” and “grade” add significantly to the prediction of self‐reported bullying; “grade” and variables measuring impaired psychosocial “well‐being” of students at school (e.g., feeling of not being popular, negative attitude towards breaks) add significantly to the prediction of self‐reported victimisation. The results are discussed against the background of other study findings, accentuating the significance of gender‐ and age‐specific forms of bullying/victimisation. Aggr. Behav. 32:1–15, 2006. © 2006 Wiley‐Liss, Inc.     

The effect of sleep deprivation on signal detection parameters

Twelve subjects performed a high signal rate vigilance task, once after a night's sleep, and once after a night without sleep. Raw scores were transformed into the signal detection parameters, d' and β. After sleep deprivation, detection performance was significantly impaired. This was reflected in a fall of d', whereas β was not significantly altered. Analysing the control data alone for comparison with other vigilance studies revealed a decrement in % signals detected and d', and an increase in β from the first to the second half of the test.