Postural coordination in looking and tracking tasks

Participants stood in a moving room and looked at a target that was attached to the front wall of the room. They were instructed either to look at the target or to track it, that is, to move so as to maintain a constant distance between the target and their head. Previous research (e.g. Bardy, Oullier, Bootsma, & Stoffregen, Journal of Experimental Psychology: Human Perception and Performance, 2002) has documented stable modes of coordination of the hip and ankle joints that emerge during the tracking task. In the present study our main goal was to determine the effects of task variation (tracking versus looking) on these postural coordination modes. Within trials, we varied the frequency of room motion between 0.10 and 0.75 Hz. The results revealed that in both the tracking and looking tasks, posture was characterized by the emergence of in-phase and anti-phase modes, although the modes were more prominent in the tracking task. For both tasks the coordination mode adopted depended on the frequency of motion of the moving room. Coupling between motion of the room and motion of the head was stronger in the tracking task than in the looking task. Overall, the dynamics of hip-ankle coordination were qualitatively similar during the looking and tracking tasks. This similarity has consequences for the development of a general theory of the visual regulation of stance.     

Methods for comparing scanpaths and saliency maps: strengths and weaknesses

In this article, we are interested in the computational modeling of visual attention. We report methods commonly used to assess the performance of these kinds of models. We survey the strengths and weaknesses of common assessment methods based on diachronic eye-tracking data. We then illustrate the use of some methods to benchmark computational models of visual attention.     

Deductive reasoning and matching-bias inhibition training: Evidence from a debiasing paradigm

Using the matching bias example, the aim of the present studies was to show that adults' reasoning biases are due to faulty executive inhibition programming. In the first study, the subjects were trained on Wason's classical card selection task; half were given training in how to inhibit the perceptual matching bias (experimental group) and half in logic without the inhibition component (control group). On the pre- and post-tests, their performance was assessed on the Evans conditional rule falsification task (with a negation in the antecedent of the rule), a task that also involves matching bias. In addition, subjects were tested for perceptual field dependence/independence using the Embedded Figures Test. The results brought out a specific inhibition training effect, as well as a clear-cut relationship in the experimental group between receptiveness to training and perceptual field independence. In the second study, the training paradigm was the same except that on the pre- and post-tests, the negation was in the consequent of the conditional rule (in this case, the perceptual matching response corresponds to the logical response). The subjects succeeded on the pre-test, and the matching-bias inhibition training had a negative effect on post-test performance. This specific negative priming effect confirms the inhibitory impact of our experimental training and outlines the dissociation of inhibition and logical components.     

Holistic face encoding is modulated by perceived face race: Evidence from perceptual adaptation

Human expertise at processing faces relies on how facial features are encoded: as a whole template rather than as a sum of independent features. This holistic encoding is less prominent for other-race faces, possibly accounting for the difficulty one encounters in recognizing these faces (the ‘other-race effect’). Here, we tested the hypothesis that the magnitude of holistic face encoding can be modulated by racial categorization of the face. Caucasian participants performed a face-composite task with ‘racially-ambiguous’ face-stimuli (cross-race morphed faces, equally categorized as Asian or Caucasian faces in an independent task). The perceived race of the ambiguous faces was manipulated using adaptation. Experiment 1 showed that identical morphed face-stimuli were processed more holistically when perceived as ‘same-race’ than as ‘other-race’, i.e., following adaptation to ‘other-race’ versus ‘same-race’, respectively. Experiment 2 ascertained that the determining factor in the observed holistic processing modulation was the race of the racially-ambiguous face as perceived, rather than expected, by the participants, which supports the idea that the holistic processing of the face-stimuli was modulated by their race-categorization at the perceptual level.     

Exploring the black box of the contingent reward leadership–performance relationship: The role of perceived justice and emotional exhaustion

Using data collected from three different sources (N = 294), we examined a model in which perceived organizational justice (distributive, procedural, and interactional) and emotional exhaustion mediate the relationship between contingent reward leadership (CRL) and two performance indicators, namely organizational citizenship behaviours (OCB) and absenteeism. We found that procedural justice mediates the negative relationship between CRL and emotional exhaustion while controlling for work overload and transformational leadership. We also found that emotional exhaustion plays a mediating role in the relationship between two dimensions of justice (procedural and interactional) and both OCB and absenteeism. Interactional justice and distributive justice were also directly linked to OCB. Implications of these findings for research on leadership, psychological health, and organizational justice are discussed.     

Sight or smell: which senses do scavenging raptors use to find food?

Animal Cognition - Raptors are usually considered to be mainly visually dependent, and the use of other sensory modalities has rarely been studied in these birds. Here, we investigated...     

Enriched housing reverses age-associated impairment of cognitive functions and tPA-dependent maturation of BDNF

Although tissue type plasminogen activator (tPA) and brain derived neurotrophic factor (BDNF) have been extensively described to influence brain outcomes in a number of disorders, their roles during physiological aging are poorly investigated. In the present study, we investigated whether maintenance of mice in different environmental conditions could influence age-associated changes in hippocampal tPA expression and BDNF maturation in relation with modifications of their cognitive performances. Our data indicate that maintenance in enriched housing led to a reversal of age-associated decrease in expression of hippocampal tPA. A subsequent increase in the level of mature BDNF and an improvement in emotional and spatial memories were observed. Taken together, these data suggest that the tPA–BDNF axis could play a critical role in the control of cognitive functions influenced both by the age and housing conditions.     

Attentional bias in post-traumatic stress disorder diminishes after symptom amelioration

Background

Avoidance and hypervigilance to reminders of a traumatic event are among the main characteristics of post-traumatic stress disorder (PTSD). Attentional bias toward aversive cues in PTSD has been hypothesized as being part of the dysfunction causing etiology and maintenance of PTSD. The aim of the present study was to investigate the cognitive strategy underlying attentional bias in PTSD and whether normal cognitive processing is restored after a treatment suppressing core PTSD symptoms.

Methods

Nineteen healthy controls were matched for age, sex and education to 19 PTSD patients. We used the emotional stroop and detection of target tasks, before and after an average of 4.1 sessions of eye movement desensitization and reprocessing (EMDR) therapy.

Results

We found that on both tasks, patients were slower than controls in responding in the presence of emotionally negative words compared to neutral ones. After symptoms removal, patients no longer had attentional bias, and responded similarly to controls.

Conclusion

These results support the existence of an attentional bias in PTSD patients due to a disengagement difficulty. There was also preliminary evidence that the disengagement was linked to PTSD symptomatology. It should be further explored whether attentional bias and PTSD involve common brain mechanisms.     

N-backer: an auditory n-back task with automatic scoring of spoken responses

The n-back task is commonly used to load working memory (WM) in dual-task and neuroimaging experiments. However, it typically involves visual presentation and buttonpress responses, making it unsuitable for combination with primary tasks that involve vision and action, such as sequential object use and other tasks of daily living. The N-backer software presented here will automatically present and score auditory–verbal n-back sequences utilising the standard speech synthesis and recognition facilities that come with Microsoft Windows. Data are presented from an experiment in which 12 student participants carried out three tasks from the Naturalistic Action Test (NAT) while their attention was divided between the primary task and a continuous auditory–verbal 2-back secondary task. The participants’ 2-back performance was scored in two ways: by hand, from video recordings, and automatically, using the software, allowing us to evaluate the accuracy of N-backer. There was an extremely high correlation between these scores (.933). The videos were also used to obtain a comprehensive error score for the NAT. Significantly more errors were made in the more complex NAT tasks when participants were 2-backing, as compared with when they were not, showing that the auditory–verbal n-back task can be used to disrupt sequential object use. This dual-task method may simulate the attentional deficits of patients with brain injury, providing insights into the difficulties they face in tasks of daily living.     

On reducing an empathy gap: the impact of self-construal and order of judgment

Empathy gaps, in which individuals exaggerate self-other similarities or differences, generate errors in social judgments. We investigated whether changing individuals' self-construal may reduce one specific empathy gap: the illusion of courage. Participants primed with independent or interdependent self-construal made judgments about their own and other people's willingness to dance in public. Participants in the interdependence condition showed a reduction of the empathy gap, but only when judging the other first. This finding highlights that simple contextual manipulations have the potential to reduce egocentric biases in social judgments.