Commentary: Musicians' online performance during auditory and visual statistical learning tasks

A commentary on: Musicians' Online Performance during Auditory and Visual Statistical Learning Tasks by Mandikal Vasuki, P. R., Sharma, M., Ibrahim, R. K., and Arciuli, J. (2017). Front. Hum. Neurosci. 11:114. doi: 10.3389/fnhum.2017.00114 Statistical learning (SL) is the extraction of the underlying statistical structure from sensory input (Frost et al., 2015). The extent to which this ability is domain-general (with a single central mechanism underpinning SL in any modality) or domain-specific (where the SL mechanism differs by modality) remains a central question in statistical learning (Frost et al., 2015), and two approaches have been adopted to tackle this. First is to examine the extent to which predominantly domain-specific skills such as language proficiency (Arciuli and von Koss Torkildsen, 2012) and musical expertise (Schön and François, 2011), and domain-general skills such as working memory and general IQ (Siegelman and Frost, 2015), correlate with SL ability. Second is to compare SL performance across modalities, or even examine cross-modal transfer (Durrant et al., 2016). Mandikal Vasuki et al. (2017) (and the sister paper: Mandikal Vasuki et al., 2016) make an important contribution by adopting both of these approaches. They compare auditory and visual SL using the Saffran triplet learning paradigm (Saffran et al., 1999) in musicians and non-musicians. The three key findings are that musicians are better than non-musicians at segmentation of auditory stimuli only, there is no correlation between auditory and visual performance, and that auditory performance is better overall. This last result could be due to privileged auditory processing of sequential stimuli (Conway et al., 2009), or it could just reflect differences in perceptual or memory capabilities across modalities. However, the fact that SL performance in one modality does not predict performance in another is hard to explain if a single mechanism underlying both is posited. Combined with the fact that overall better performance was found in musicians only in the auditory modality, a domain-specific SL mechanism seems to offer the most parsimonious explanation of this data

Age-of-actor effect in body expression recognition of children

Investigations of developmental trajectories for emotion recognition suggest that both face- and body expression recognition increases rapidly in early childhood and reaches adult levels of performance near the age of ten. So far, little is known about whether children's ability to recognise body expressions is influenced by the age of the person they are observing. This question is investigated here by presenting 119 children and 42 young adults with videos of children, young adults and older adults expressing emotions with their whole body. The results revealed an own-age advantage for children, reflected in adult-level accuracy for videos of children for most expressions but reduced accuracy for videos of older adults. Children's recognition of older adults' expressions was not correlated with children's estimated amount of contact with older adults. Support for potential influences of social biases on performance measures was minimal. The own-age advantage was explained in terms of children's reduced familiarity with body expressions of older adults due to aging related changes in the kine�matics characteristics of movements and potentially due to stronger embodiment of other children's bodily movements

The Cognitive Daisy – a novel method for recognising the cognitive status of older adults in residential care: Innovative practice

The Cognitive Daisy (COG-D) is an innovative assessment system created to provide healthcare staff with an instant snapshot of the cognitive status of older adults in residential care. The COG-D comprises a flower head consisting of 15 colour coded petals depicting information about: visual-spatial perception, comprehension, communication, memory and attention. This study confirmed the practicality of the COG-D protocol for assessing cognition in a sample of 33 older adults living in residential care and endorsed the use of the COG-D as a tool for recognising the cognitive status of care home residents

Distinguishing between knowledge gaps and misconceptions of Alzheimer’s disease among caregivers in the UK

A popular scale for assessing knowledge about Alzheimer‘s disease is the Alzheimer‘s Disease Knowledge Scale (ADKS). The aim of the study was to investigate the effect of adding ‗don‘t know‘ to the original ‗true‘ or ‗false‘ response option. It was assumed that this modification would provide insight into the reasons underlying incorrect responses and could distinguish between misconceptions and knowledge gaps. To investigate this, carers (care home carers and informal carers) and members of the general population were recruited. The results showed that percentage correct responses was lower than previously reported, suggesting potential inflation of knowledge by guesses without the ‗don‘t know‘ option. Moreover, care-home workers were more likely to select the incorrect response than ‗don‘t know‘ compared to informal carers for several items related to the earlier stages of AD, suggesting a higher level of misconceptions around this topic and highlighting potential training needs for care home carers

Generating ogives to (i) analyse perceptual changes associated with ambiguous figures, and (ii) reaction times in an inhibition-of-return (IOR) task

The perceptual changes (PCs) associated with viewing an ambiguous figure like the Necker cube (NC) can be considered as a series of independent events in time. The time between successive PCs is then percept duration, and the frequency distribution of percepts plotted against duration is adequately modelled by a gamma distribution (Borsellino et al, 1972 Kybernetik 10 139 - 144). A logarithmic transformation on the duration scale enabled us to model the subsequent distribution with a Gaussian. The cumulative Gaussian fitted to the normalised ogive allowed simple comparison of observer performance in different conditions. We found no differences between ogives generated for the standard 'cube-up' and 'cube-down' 3-D perceptual alternatives. When observers recorded 2-D perceptual alternatives, the ogives were shallower and shifted to the right. This suggests that the neural mechanisms governing PCs between 3-D and 2-D perceptual alternatives differ from those that govern the PCs between the opposing 3-D perceptual alternatives of 'cube-up' and 'cube-down'. Further, we show that the same analysis can be applied to reaction times generated in an inhibition-of-return (IOR) task. We argue that this form of analysis is superior to other more commonly reported methods for both attentional and PC data

Event-related potential correlates of spatiotemporal regularities in vision

Spatiotemporal regularities in stimulus structure have been shown to influence visual target detection and discrimination. Here we investigate whether the influence of spatiotemporal regularity is associated with the modulation of early components (P1/N1) in Event-Related Potentials (ERP). Stimuli consisted of five horizontal bars (predictors) appearing successively towards the fovea followed by a target bar at fixation, and participants performed a key-press on target detection. Results showed that compared to the condition where five predictors were presented in a temporally regular but spatially randomised order, target detection-times were faster and contralateral N1 peak latencies were shorter when the predictors and the target were presented with spatial and temporal regularity. Both measures were most prolonged when only the target was presented. In this latter condition, an additional latency prolongation was observed for the P1 peak compared to the conditions where the target was preceded by the predictors. The latency shifts associated with early ERP components provides additional support for involvement of early visual processing stages in the coding of spatiotemporal regularities in humans

Behavioural and physiological correlates of impulsivity in the domestic dog (Canis familiaris)

Impulsivity is a trait related to inhibitory control which is expressed in a range of behaviours. Impulsive individuals show a decreased ability to tolerate delay of reinforcement, and more impulsive behaviour has been linked to decreased levels of serotonin and dopamine in a number of species. In domestic dogs, impulsivity is implicated in problem behaviours that result from a lack of self control, but currently there are no published studies that assess behavioural and physiological measures of impulsivity in relation to this trait. Impulsivity scores were calculated for 41 dogs using an owner-report assessment, the Dog Impulsivity Assessment Scale (DIAS). Twenty-three of these subjects completed an operant choice task based on a delayed reward paradigm, to assess their tolerance to delay of reinforcement. High Pressure Liquid Chromatography (HPLC) with Fluorometric Detection was used to detect levels of the metabolites of serotonin (5-HIAA) and dopamine (HVA) in the urine of 17 of the subjects. Higher impulsivity scores were found to be significantly correlated with more impulsive behaviour (reduced tolerance to delay of reinforcement) in the behaviour tests and lower levels of urinary 5-HIAA and 5-HIAA/HVA ratio. The results demonstrate convergent validity between impulsivity (as assessed by the DIAS) and behavioural and physiological parameters

Influence of hand position on the near-effect in 3D attention

Voluntary reorienting of attention in real depth situations is characterized by an attentional bias to locations near the viewer once attention is deployed to a spatially cued object in depth. Previously this effect (initially referred to as the ‘near-effect’) was attributed to access of a 3D viewer-centred spatial representation for guiding attention in 3D space. The aim of this study was to investigate whether the near-bias could have been associated with the position of the response-hand, always near the viewer in previous studies investigating endogenous attentional shifts in real depth. In Experiment 1, the response-hand was placed at either the near or far target depth in a depth cueing task. Placing the response-hand at the far target depth abolished the near-effect, but failed to bias spatial attention to the far location. Experiment 2 showed that the response-hand effect was not modulated by the presence of an additional passive hand, whereas Experiment 3 confirmed that attentional prioritization of the passive hand was not masked by the influence of the responding hand on spatial attention in Experiment 2. The pattern of results is most consistent with the idea that response preparation can modulate spatial attention within a 3D viewer-centred spatial representation

Gaze patterns in viewing static and dynamic body expressions

Evidence for the importance of bodily cues for emotion recognition has grown over the last two decades. Despite this growing literature, it is underspecified how observers view whole bodies for body expression recognition. Here we investigate to which extent body-viewing is face- and context-specific when participants are categorizing whole body expressions in static (Experiment 1) and dynamic displays (Experiment 2). Eye-movement recordings showed that observers viewed the face exclusively when visible in dynamic displays, whereas viewing was distributed over head, torso and arms in static displays and in dynamic displays with faces not visible. The strong face bias in dynamic face-visible expressions suggests that viewing of the body responds flexibly to the informativeness of facial cues for emotion categorisation. However, when facial expressions are static or not visible, observers adopt a viewing strategy that includes all upper body regions. This viewing strategy is further influenced by subtle viewing biases directed towards emotion-specific body postures and movements to optimise recruitment of diagnostic information for emotion categorisation

Facial expression training optimises viewing strategy in children and adults

This study investigated whether training-related improvements in facial expression categorization are facilitated by spontaneous changes in gaze behaviour in adults and nine-year old children. Four sessions of a self-paced, free-viewing training task required participants to categorize happy, sad and fear expressions with varying intensities. No instructions about eye movements were given. Eye-movements were recorded in the first and fourth training session. New faces were introduced in session four to establish transfer-effects of learning. Adults focused most on the eyes in all sessions and increased expression categorization accuracy after training coincided with a strengthening of this eye-bias in gaze allocation. In children, training-related behavioural improvements coincided with an overall shift in gaze-focus towards the eyes (resulting in more adult-like gaze-distributions) and towards the mouth for happy faces in the second fixation. Gaze-distributions were not influenced by the expression intensity or by the introduction of new faces. It was proposed that training enhanced the use of a uniform, predominantly eyes-biased, gaze strategy in children in order to optimise extraction of relevant cues for discrimination between subtle facial expressions