Spatial attention shifting and phonological processing in adults with dyslexia

According to Hari and Renvall’s (2001) sluggish attentional shifting (SAS) hypothesis people with dyslexia have a central deficit in attention shifting. Here we assessed whether a group of adults with dyslexia showed impaired performance on shifting visual spatial attention. Twelve adults with dyslexia and 12 control adult participants took part in a Posner style focused attention orientation task and a shift attention orientation task. The participants also completed standardized measures of single word reading, spelling, IQ, phonological processing, speed of processing and non-word reading. Overall, the dyslexic participants showed the same pattern of performance as the control participants on the attention-orienting task, but completed the tasks at a consistently slower pace. Specifically, participants in both groups found short target presentation intervals more difficult than longer target presentation intervals, and participants in both groups were more impaired when cue-to-target information was invalid 20% of the time (shift task) than when it was valid all of the time (focused task). However, the group with dyslexia was significantly more impaired across the board

Understanding earwitness testimony

Most students are familiar with eyewitness testimony, but earwitness testimony might be valuable too. Cognitive specialist Andrew K. Dunn considers the evidence

Matching novel face and voice identity using static and dynamic facial images

Research investigating whether faces and voices share common source identity information has offered contradictory results. Accurate face-voice matching is consistently above chance when the facial stimuli are dynamic, but not when the facial stimuli are static. We tested whether procedural differences might help to account for the previous inconsistencies. In Experiment 1, participants completed a sequential two-alternative forced choice matching task. They either heard a voice and then saw two faces or saw a face and then heard two voices. Face – voice matching was above chance when the facial stimuli were dynamic and articulating, but not when they were static. In Experiment 2, we tested whether matching was more accurate when faces and voices were presented simultaneously. The participants saw two face–voice combinations, presented one after the other. They had to decide which combination was the same identity. As in Experiment 1, only dynamic face–voice matching was above chance. In Experiment 3, participants heard a voice and then saw two static faces presented simultaneously. With this procedure, static face–voice matching was above chance. The overall results, analyzed using multilevel modeling, showed that voices and dynamic articulating faces, as well as voices and static faces, share concordant source identity information. It seems, therefore, that above-chance static face–voice matching is sensitive to the experimental procedure employed. In addition, the inconsistencies in previous research might depend on the specific stimulus sets used; our multilevel modeling analyses show that some people look and sound more similar than others

Effects of pathogen priming on judgements of face and voice attractiveness and health [oral presentation]

It has been shown (e.g. Wells et al., 2011) that whilst individuals can use both face and voice quality to make judgements of perceived attractiveness and health, in face-voice compounds, face quality typically overshadows (dominates) the judgement. It has also been shown that priming about environmental pathogen load can have a significant effect on a range judgements and behaviours (e.g. Dunn & Chambers, 2011; Little et al., 2011). Here we report on two experiments (Exp. 1 & Exp. 2), in which we explored the effects of implicit pathogen priming on face/voice attractiveness ratings (Exp. 1) and voice health ratings (Exp. 2). In Exp. 1 we show that although average attractiveness ratings for component (face or voice) and compound (face-voice) targets do not significantly change, following priming, the amount of variance accounted for by the component voice ratings in relation to the compound face-voice ratings, significantly increased, thereby removing face overshadowing. In Exp. 2 we show that whilst priming significantly shifts voice health judgements, relative to baseline, there is also a significant difference between priming the past environment (time of target stimulus collection) or the present environment (time of rating). The difference was such that priming the past produced a significantly smaller shift in voice ratings than priming the present. The findings from both experiments demonstrate that personal preference changes when pathogen load is perceived to be high, and that temporal information mediates this influence. These findings are consistent with a behavioural immune system hypothesis (e.g. Schaller & Duncan 2007)

Near or far away? A proximity and emotion, not size and emotion effect using Russian dolls [poster presentation]

The size and emotion effect is the tendency for children to draw people/objects with a positive emotional charge larger than those with a negative or neutral charge. Here we explored the novel idea that drawing size might be acting as a proxy for depth (physical or perceived), in a 2D environment. Forty-two children (aged 3-11 years) chose, from 2 sets of Matryoshka dolls, a doll to represent a person with positive, negative or neutral charge, which they placed in front of themselves on a sheet of 3A paper. We found that the children used proximity and not perceived depth or size, to indicate emotional charge. This is consistent with the notion that, in drawings, children may be using size as a proxy for physical closeness (proximity) as they attempt, with varying success, to put positive charged items closer to, or negative and neutral charge items further away from, themselves

Integrated processes in person perception: matching novel faces and voices [oral presentation]

A series of studies investigated whether people can match novel faces and voices of the same age (20-30) and sex at a level significantly above chance. The studies also tested whether accuracy is affected by facial stimuli type: static or moving, and the order of stimuli presentation: face first or voice first. In Experiment 1 participants saw a face and heard a voice one after the other. They had to decide whether the stimuli were matching or not matching. When the correct matching stimulus was present participants consistently performed above chance level, regardless of facial stimuli type or stimuli order. When the correct matching stimulus was not present participants were either just guessing (voice first) or significantly below chance (face first). In Experiment 2 and 3 participants had to select the correct matching stimuli in a two-alternative forced choice task. The correct matching stimuli was always present in Experiment 2. It was never present in Experiment 3. Experiments 2 and 3 replicated the results of Experiment 1. Participants in Experiment 2 were more accurate when the correct matching stimulus was present in position 1. Experiment 3 showed that a response bias was operating; participants selected stimulus 1 more often than stimulus 2. However, the bias did not wholly explain the overall above-chance accuracy levels in Experiment 2. This set of results show that people can accurately match novel faces and voices, indicating that faces and voices offer concordant information. Face and voice perception appears to be an integrated process

Development of a Body Dissatisfaction Scale assessment tool

The present research details the development of a new pictorial scale (Body Dissatisfaction Scale) to be used in the measurement of body dissatisfaction. The scale comprises nine female and nine male images of computer generated bodies that increase successively in body weight. Using a sample of 190 students female = 130, male = 60) results showed that the new scale exhibits good validity, with participants being able to correctly identify body weight differences between all bodies in the scale. Evidence for construct validity was demonstrated by significant correlations between ratings of perceived actual body size using the current scale and participants' BMI. Body dissatisfaction measured using the current scale was also negatively correlated with a measure of body appreciation. Test-retest reliability remained stable over a 5 week period. The scale improves on previous pictorial scales by offering both male and female versions while offering improved realism and consistency between images

Searching for pitch invariant representations in auditory cortex [oral presentation]

Pitch constancy relates to perceiving the same pitch from tones with differing spectral shapes and is one key criteria for identifying a pitch selective neural representation in auditory cortex. Here we used an event-related potential (ERP) adaptation study and a behavioural task (target same/different) to investigate whether pitch coding is invariant to changes in timbre. Adaptation is observed as a decrease in N100-P200 when the same stimulus is repeated because overlapping neuronal populations encode the stimulus. Reduced adaptation indicates that new neuronal populations are recruited to encode a change in an acoustic feature of interest (i.e. pitch, timbre or both). If neurons are selective to pitch (invariant to timbre), reduced adaptation should occur for pitch changes only. If selective to both (non-invariant to timbre), reduced adaptation should occur for pitch and timbre changes. Similarly, stimulus discrimination during the behavioural task should not require any additional processing resources if neurons are selective to pitch only, and hence reaction times and accuracy should be equivalent across conditions. If neurons are selective to both pitch and timbre, longer reaction times and poorer accuracy should be observed for timbre changes. We found reduced adaptation in the N100-P200 and increased reaction times and poorer accuracy for timbre changes. This suggests that neurons in auditory cortex are selective to both pitch and timbre, i.e. pitch coding is non-invariant to timbre. This supports recent evidence suggesting interdependence between pitch