Application of the rubber hand illusion paradigm: comparison between upper and lower limbs

The “rubber hand illusion (RHI)” is a perceptual illusion, which allows the integration of artificial limbs into the body representation of a person by means of combined visual and tactile stimulation. The illusion has been frequently replicated but always concerning the upper limbs. The present study verified an analog illusion that can be called the “rubber foot illusion” (RFI). In a conjoint experiment using both a rubber hand and a rubber foot, brushstrokes were applied to the respective real and rubber limb placed alongside the real one. However, only the artificial limb’s handling was visible. The brushstrokes were given either synchronously, with a delay of ±0.5 s, or without tactile stimulation of the real limb. Questionnaire data and the proprioceptive drift towards the rubber limb (determined by calling on the subjects to show where they locate their unseen limb) defined the illusion strength. Results revealed that the illusion was induced in both limbs with comparable strength, but only in the synchronous condition.     

The relationship between prospective memory and episodic future thinking in younger and older adulthood

Episodic future thinking (EFT), the ability to project into the future to “preexperience” an event, and prospective memory (PM), remembering to perform an intended action, are both examples of future-oriented cognition. Recently it has been suggested that EFT might contribute to PM performance but to date few studies have examined the relationship between these two capacities. The aim of the present study was to investigate the nature and specificity of this relationship, as well as whether it varies with age. Participants were 125 younger and 125 older adults who completed measures of EFT and PM. Significant, positive correlations between EFT and PM were identified in both age groups. Furthermore, EFT ability accounted for significant unique variance in the young adults, suggesting that it may make a specific contribution to PM function. Within the older adult group, EFT did not uniquely contribute to PM, possibly indicating a reduced capacity to utilize EFT, or the use of compensatory strategies. This study is the first to provide systematic evidence for an association between variation in EFT and PM abilities in both younger and older adulthood and shows that the nature of this association varies as a function of age.     

Behavioral and physiological responses of young horses to different weaning protocols: a pilot study

In this study, effects of weaning on behavioral and physiological stress parameters in young horses (foals) were determined. Foals were weaned either simultaneously without the presence of adult horses (group A, n?=?6), or in the presence of two adult females familiar but unrelated to the foals (group B, n?=?5), or weaned consecutively by removing two mother horses per day (group C, n?=?6). Behavior, locomotion, salivary cortisol concentration, beat-to-beat (RR) interval, heart rate variability (HRV) and weight were determined. Group A foals lost weight for 2 days (mean?±?SEM) -?8.3?±?1.6?kg, p?相似文献   

Time of day effects on problem solving: When the non-optimal is optimal

In a study examining the effects of time of day on problem solving, participants solved insight and analytic problems at their optimal or non-optimal time of day. Given the presumed differences in the cognitive processes involved in solving these two types of problems, it was expected that the reduced inhibitory control associated with non-optimal times of the day would differentially impact performance on the two types of problems. In accordance with this expectation, results showed consistently greater insight problem solving performance during non-optimal times of day compared to optimal times of day but no consistent time of day effects on analytic problem solving. The findings indicate that tasks involving creativity might benefit from a non-optimal time of day.     

Future thinking instructions improve prospective memory performance in adolescents

Studies on prospective memory (PM) development in adolescents point to age-related increases through to adulthood. The goal of the present study was to examine whether instructing adolescents to engage in an episodic prospection of themselves executing future actions (i.e., future thinking) when forming an intention would improve their PM performance and reduce age-related differences. Further, we set out to explore whether future thinking instructions result in stronger memory traces and/or stronger cue–context associations by evaluating retrospective memory for the PM cues after task completion and monitoring costs during PM task processing. Adolescents and young adults were allocated to either the future thinking, repeated-encoding or standard condition. As expected, adolescents had fewer correct PM responses than young adults. Across age groups, PM performance in the standard condition was lower than in the other encoding conditions. Importantly, the results indicate a significant interaction of age by encoding condition. While adolescents benefited most from future thinking instructions, young adults performed best in the repeated-encoding condition. The results also indicate that the beneficial effects of future thinking may result from deeper intention-encoding through the simulation of future task performance.     

Behavioral phenotyping of a murine model of Alzheimer’s disease in a seminaturalistic environment using RFID tracking

Neurodegen erative disorders such as Alzheimer’s disease (AD) are increasingly threatening public health. Most animal models of AD consist of transgenic mice that are usually housed singly or in unisexual groups in small barren cages. Such restricted environments, however, prevent the mice from showing a variety of speciesspecific behaviors and consequently may constrain comprehensive behavioral phenotyping. On the other hand, allowing the animals to freely organize their lives in a spacious physically and socially enriched environment makes behavioral phenotyping laborious and time consuming. Radio frequency identification (RFID) using a network of antennae and small glass-coated transponders labeling each individual allows for gathering spatiotemporal information about a large number of individuals in parallel. The aim of this project was to use the RFID technique to facilitate the characterization of mice carrying a genetic disposition to develop AD-like pathology and of their wild-type conspecifics in a spacious seminaturalistic environment.     

Incentives improve performance on both incremental and insight problem solving

An increasing number of studies are showing a connection between emotion and motivation and cognitive processes. Most of these studies, however, have been correlational in nature, limiting the conclusions that can be drawn. We directly manipulated motivation through the use of an incentive and investigated its effects on insight and incremental problem solving. In four experiments we found that an incentive (the opportunity to leave the experiment early) increased problem-solving performance for all problems presented, regardless of problem type. Additionally, we found evidence that the incentive increased recall memory, indicating more thorough processing for participants in the incentive condition. This study provides evidence that incentives influence problem solving and implies that motivation should not be ignored when investigating cognitive processes.     

Ongoing development of social cognition in adolescence

Age differences in social cognition between adolescents and young adults were investigated. Two large groups of adolescents and young adults were given tasks of theory of mind and emotion recognition. In addition, to control for possibly related basic cognitive development, working memory, speed of processing, and verbal ability were assessed. A strong age effect was revealed across both measures of social cognition. Adolescents performed with a lower accuracy than adults. Further analyses indicated that those age differences remained significant even after controlling for basic cognitive abilities. Exploratory analyses indicated no influence of pubertal phase on social cognition. Results suggest ongoing development of social cognition across adolescence, independent of individual differences in more basic cognitive abilities.     

To do or not to do? Prospective memory versus response inhibition in autism spectrum disorder and attention-deficit/hyperactivity disorder

In the present research, event-based prospective memory and response inhibition (RI) abilities were investigated in children with ASD (Study 1), with ADHD (Study 2), and their matched neurotypical controls. Children engaged in a categorisation (ongoing) task and, concurrently, in either an event-based prospective memory (PM) or a Go/No-Go secondary task. Results showed that, as compared to their matched controls, ASD children's performance was more impaired in the PM task than in the Go/No-Go task, while the performance pattern of ADHD children was reversed. In the ongoing task, ASD children were as accurate as, but significantly slower than, controls, independently of conditions. ADHD children did not differ from controls in the presence of a concurrent PM task, while they were less accurate than controls in the presence of the go/no-go task. Overall, the two patterns of findings suggest important differences in the way ASD and ADHD children remember and realise intentions requiring opposite behaviours (acting vs stopping).