A new set of illusions--the dynamic luminance-gradient illusion and the breathing light illusion

A novel set of illusions that break brightness constancy and size constancy at the same time is reported. The illusions occur when observers move towards or away from these patterns. Many variations of these phenomena and a possible explanation are discussed.     

Neurodisruption of selective attention: insights and implications

Mechanisms of selective attention are vital for coherent perception and action. Recent advances in cognitive neuroscience have yielded key insights into the relationship between neural mechanisms of attention and eye movements, and the role of frontal and parietal brain regions as sources of attentional control. Here we explore the growing contribution of reversible neurodisruption techniques, including transcranial magnetic stimulation and microelectrode stimulation, to the cognitive neuroscience of spatial attention. These approaches permit unique causal inferences concerning the relationship between neural processes and behaviour, and have revealed fundamental mechanisms of attention in the human and animal brain. We conclude by suggesting that further advances in the neuroscience of attention will be facilitated by the combination of neurodisruption techniques with established neuroimaging methods.     

Differentiation of classical music requires little learning but rhythm

Detecting distinctions between the styles of classical music (e.g. Baroque and Romantic) is often viewed as the privilege of musicians. However, this elite perspective underestimates the abilities of non-musicians. We report that Western musicians and non-musicians, and non-Westerners (i.e. Chinese participants) rated pairs of excerpts presented auditorily as more similar as their compositional styles were closer in history. Moreover, the styles were considered by all participants as more different when presented in historical order, the older style preceding the more recent style (e.g. Baroque followed by Romantic), than the reverse (e.g. Romantic followed by Baroque). This historical distance effect appears related to rhythm (or temporal variability).     

Friendship closeness inventory: development and psychometric evaluation

This study developed a psychometrically sound measure of closeness in Australian men's (n = 59) and women's (n = 77) same-sex friendships, the Friendship Closeness Inventory. Subscales were developed to measure both masculine and feminine styles of closeness in three domains of Emotional Closeness, Behavioural Closeness, and Cognitive Closeness. The inventory was subjected to reliability checks which supported the reliability of each scale, and factor analyses which supported the 3-factor design. Correlations among ratings on subscales suggested that the affective, behavioural, and cognitive dimensions are distinguishable but related components of friendship. Group comparisons indicated that women rated themselves closer to their same-sex friends on the affective dimension than men. Researchers have suggested that sex-role socialisation may partly account for sex differences in self-ratings of emotional expressiveness in friendships. There were no significant differences between men's and women's ratings on the behavioural and cognitive aspects of friendships. The cognitive element may need further exploration in further scale development as it measures only one aspect of cognitive closeness: the perceived influence of friends. Pending further validation, the inventory appears potentially useful for research exploring affective, behavioural, and cognitive elements of young men's and women's friendships.     

Diffusion and induced magnetic anisotropy in nanocrystalline Fe73.5Si13.5B9Nb3Cu1

⁷¹Ge tracer diffusion was studied to gain insight into the atomistic transport processes underlying the formation of magnetic anisotropy in nanocrystalline soft-magnetic Fe_73.5Si_13.5B₉Nb₃Cu₁. The interfacial diffusion characteristic was determined by the residual intergranular amorphous phase, which gives rise to a strongly reduced interface diffusivity compared with grain boundaries in metals. Ge diffusion in the nanocrystallites, which is considered to characterize Si self-diffusion, is much slower than Fe diffusion owing to the D0₃ order of the Fe₃Si nanocrystallites. Slow Si diffusion in the nanocrystallites is identified as the rate-controlling process for the generation of the field-induced magnetic anisotropy.     

Musical groove modulates motor cortex excitability: A TMS investigation

Groove is often described as a musical quality that can induce movement in a listener. This study examines the effects of listening to groove music on corticospinal excitability. Musicians and non-musicians listened to high-groove music, low-groove music, and spectrally matched noise, while receiving single-pulse transcranial magnetic stimulation (TMS) over the primary motor cortex either on-beat or off-beat. We examined changes in the amplitude of the motor-evoked potentials (MEPs), recorded from hand and arm muscles, as an index of activity within the motor system. Musicians and non-musicians rated groove similarly. MEP results showed that high-groove music modulated corticospinal excitability, whereas no difference occurred between low-groove music and noise. More specifically, musicians’ MEPs were larger with high-groove than low-groove music, and this effect was especially pronounced for on-beat compared to off-beat pulses. These results indicate that high-groove music increasingly engages the motor system, and the temporal modulation of corticospinal excitability with the beat could stem from tight auditory–motor links in musicians. Conversely, non-musicians’ MEPs were smaller for high-groove than low-groove music, and there was no effect of on- versus off-beat pulses, potentially stemming from suppression of overt movement. In sum, high-groove music engages the motor system, and previous training modulates how listening to music with a strong groove activates the motor system.     

Brain correlates of subjective freedom of choice

The subjective feeling of free choice is an important feature of human experience. Experimental tasks have typically studied free choice by contrasting free and instructed selection of response alternatives. These tasks have been criticised, and it remains unclear how they relate to the subjective feeling of freely choosing. We replicated previous findings of the fMRI correlates of free choice, defined objectively. We introduced a novel task in which participants could experience and report a graded sense of free choice. BOLD responses for conditions subjectively experienced as free identified a postcentral area distinct from the areas typically considered to be involved in free action. Thus, the brain correlates of subjective feeling of free action were not directly related to any established brain correlates of objectively-defined free action. Our results call into question traditional assumptions about the relation between subjective experience of choosing and activity in the brain’s so-called voluntary motor areas.     

Acquiring Non-Object Terms: The Case for Time Words

We address the issue of children's understanding of abstract words with two studies on preschoolers' knowledge of the time-duration words minutes, hours, days, and years. The first study examines 4- and 5-year-olds' ability to answer questions about durations of common phenomena with duration terms. The second study examines 4- to 6-year-olds' comprehension of duration terms with a forced-choice pointing task. Both show that preschoolers' knowledge of such words is incomplete, but that it adheres to the pattern proposed in previous work with toddlers for abstract words. More specifically, children form lexical domains for such words even before they know their individual meanings, thereby allowing the children to often respond appropriately but not usually correctly to questions about abstract dimensions like time.     

Motor Processes in Children's Mental Rotation

Previous studies with adult human participants revealed that motor activities can influence mental rotation of body parts and abstract shapes. In this study, we investigated the influence of a rotational hand movement on mental rotation performance from a developmental perspective. Children at the age of 5, 8, and 11 years and adults performed a mental rotation task while simultaneously rotating their hand (guided by a handle). The direction of the manual rotation was either compatible or incompatible with the direction of the mental rotation. Response times increased with increasing stimulus orientation angles, indicating that participants of all age groups used mental rotation to perform the task. A differential effect of the compatibility of manual rotation and mental rotation was found for 5-year-olds and 8-year-olds, but not for 11-year-olds and adults. The results of this study suggest that the ability to dissociate motor from visual cognitive processes increases with age.     

Perceptual load in sport and the heuristic value of the perceptual load paradigm in examining expertise-related perceptual-cognitive adaptations

In two experiments, we transferred perceptual load theory to the dynamic field of team sports and tested the predictions derived from the theory using a novel task and stimuli. We tested a group of college students (N = 33) and a group of expert team sport players (N = 32) on a general perceptual load task and a complex, soccer-specific perceptual load task in order to extend the understanding of the applicability of perceptual load theory and further investigate whether distractor interference may differ between the groups, as the sport-specific processing task may not exhaust the processing capacity of the expert participants. In both, the general and the specific task, the pattern of results supported perceptual load theory and demonstrates that the predictions of the theory also transfer to more complex, unstructured situations. Further, perceptual load was the only determinant of distractor processing, as we neither found expertise effects in the general perceptual load task nor the sport-specific task. We discuss the heuristic utility of using response-competition paradigms for studying both general and domain-specific perceptual-cognitive adaptations.