Realism of Confidence,Modes of Apprehension,and Variable-Use in Visual Discrimination of Relative Mass

We investigated the role of movement in the perception of a novel affordance for wheelchair locomotion. Healthy adults without prior wheelchair experience judged the lowest lintel under which they could roll in the wheelchair. Prior to judgments, some participants were given brief (~2 min) practice at self-controlled wheelchair locomotion. There were 2 main results. First, participants who had this brief practice accurately judged their own minimum passage height (even when practice did not include passage under low lintels), whereas participants who had no practice gave inaccurate judgments. Second, prejudgment practice strongly influenced movement of the head and torso during judgment sessions. The results demonstrate that affordance perception can be learned through brief, indirect practice and suggest that such practice can inform exploratory movement.     

Emotional mimicry of older adults’ expressions: effects of partial inclusion in a Cyberball paradigm

As intergenerational interactions increase due to an ageing population, the study of emotion-related responses to the elderly is increasingly relevant. Previous research found mixed results regarding affective mimicry – a measure related to liking and affiliation. In the current study, we investigated emotional mimicry to younger and older actors following an encounter with a younger and older player in a Cyberball game. In a complete exclusion condition, in which both younger and older players excluded the participant, we expected emotional mimicry to be stronger for younger vs. older actors. In a partial inclusion condition, in which the younger player excluded while the older player included the participant, we predicted that the difference in player behaviour would lead to a difference in liking. This increased liking of the older interaction partner should reduce the difference in emotional mimicry towards the two different age groups. Results revealed more mimicry for older actors following partial inclusion especially for negative emotions, suggesting inclusive behaviour by an older person in an interaction as a possible means to increase mimicry and affiliation to the elderly.     

A role for Synapsin in associative learning: the Drosophila larva as a study case

Synapsins are evolutionarily conserved, highly abundant vesicular phosphoproteins in presynaptic terminals. They are thought to regulate the recruitment of synaptic vesicles from the reserve pool to the readily-releasable pool, in particular when vesicle release is to be maintained at high spiking rates. As regulation of transmitter release is a prerequisite for synaptic plasticity, we use the fruit fly Drosophila to ask whether Synapsin has a role in behavioral plasticity as well; in fruit flies, Synapsin is encoded by a single gene (syn). We tackled this question for associative olfactory learning in larval Drosophila by using the deletion mutant syn^97CS, which had been backcrossed to the Canton-S wild-type strain (CS) for 13 generations. We provide a molecular account of the genomic status of syn^97CS by PCR and show the absence of gene product on Western blots and nerve-muscle preparations. We found that olfactory associative learning in syn^97CS larvae is reduced to ~50% of wild-type CS levels; however, responsiveness to the to-be-associated stimuli and motor performance in untrained animals are normal. In addition, we introduce two novel behavioral control procedures to test stimulus responsiveness and motor performance after “sham training.” Wild-type CS and syn^97CS perform indistinguishably also in these tests. Thus, larval Drosophila can be used as a case study for a role of Synapsin in associative learning.     

Sensory laterality in affiliative interactions in domestic horses and ponies (<Emphasis Type="Italic">Equus caballus</Emphasis>)

Many studies have been carried out into both motor and sensory laterality of horses in agonistic and stressful situations. Here we examine sensory laterality in affiliative interactions within four groups of domestic horses and ponies (N?=?31), living in stable social groups, housed at a single complex close to Vienna, Austria, and demonstrate for the first time a significant population preference for the left side in affiliative approaches and interactions. No effects were observed for gender, rank, sociability, phenotype, group, or age. Our results suggest that right hemisphere specialization in horses is not limited to the processing of stressful or agonistic situations, but rather appears to be the norm for processing in all social interactions, as has been demonstrated in other species including chicks and a range of vertebrates. In domestic horses, hemispheric specialization for sensory input appears not to be based on a designation of positive versus negative, but more on the perceived need to respond quickly and appropriately in any given situation.     

Judging the animacy of words: The influence of typicality and age of acquisition in a semantic decision task

The age at which members of a semantic category are learned (age of acquisition), the typicality they demonstrate within their corresponding category, and the semantic domain to which they belong (living, non-living) are known to influence the speed and accuracy of lexical/semantic processing. So far, only a few studies have looked at the origin of age of acquisition and its interdependence with typicality and semantic domain within the same experimental design. Twenty adult participants performed an animacy decision task in which nouns were classified according to their semantic domain as being living or non-living. Response times were influenced by the independent main effects of each parameter: typicality, age of acquisition, semantic domain, and frequency. However, there were no interactions. The results are discussed with respect to recent models concerning the origin of age of acquisition effects.     

The Affect Misattribution Procedure: hot or not?

The Affect Misattribution Procedure (AMP; Payne, Cheng, Govorun, & Stewart, 2005) is an important tool in implicit social cognition research, but little is known about its underlying mechanisms. This paper investigates whether, as the name implies, affect-based processes really underlie the AMP. We used a modified AMP that enabled us to separate the influence of affective and nonaffective processes. In three studies, evidence for the implication of nonaffective processes was consistently found. In contrast, there was no evidence for affect-based processes. Thus, the AMP rather seems cold than hot. The generalizability of the results obtained with the modified AMP is discussed.     

Insular activity during passive viewing of aversive stimuli reflects individual differences in state negative affect

People differ with regard to how they perceive, experience, and express negative affect. While trait negative affect reflects a stable, sustained personality trait, state negative affect represents a stimulus limited and temporally acute emotion. So far, little is known about the neural systems mediating the relationship between negative affect and acute emotion processing. To address this issue we investigated in a healthy female sample how individual differences in state negative affect are reflected in changes in blood oxygen level-dependent responses during passive viewing of emotional stimuli. To assess autonomic arousal we simultaneously recorded changes in skin conductance level. At the psychophysiological level we found increased skin conductance level in response to aversive relative to neutral pictures. However, there was no association of state negative affect with skin conductance level. At the neural level we found that high state negative affect was associated with increased left insular activity during passive viewing of aversive stimuli. The insula has been implicated in interoceptive processes and in the integration of sensory, visceral, and affective information thus contributing to subjective emotional experience. Greater recruitment of the insula in response to aversive relative to neutral stimuli in subjects with high state negative affect may represent increased processing of salient aversive stimuli.