Short-term memory, executive control, and children's route learning

The aim of this study was to investigate route-learning ability in 67 children aged 5 to 11years and to relate route-learning performance to the components of Baddeley's model of working memory. Children carried out tasks that included measures of verbal and visuospatial short-term memory and executive control and also measures of verbal and visuospatial long-term memory; the route-learning task was conducted using a maze in a virtual environment. In contrast to previous research, correlations were found between both visuospatial and verbal memory tasks-the Corsi task, short-term pattern span, digit span, and visuospatial long-term memory-and route-learning performance. However, further analyses indicated that these relationships were mediated by executive control demands that were common to the tasks, with long-term memory explaining additional unique variance in route learning.     

The development of route learning in Down syndrome,Williams syndrome and typical development: investigations with virtual environments

The ability to navigate new environments has a significant impact on the daily life and independence of people with learning difficulties. The aims of this study were to investigate the development of route learning in Down syndrome (N = 50), Williams syndrome (N = 19), and typically developing children between 5 and 11 years old (N = 108); to investigate use of landmarks; and to relate cognitive functions to route‐learning ability in these groups. Overall, measures of attention and long‐term memory were strongly associated with route learning, even once non‐verbal ability was controlled for. All of the groups, including 5‐ to 6‐year‐old TD children, demonstrated the ability to make use of all landmark types to aid route learning; those near junctions, those further from junctions, and also distant landmarks (e.g. church spire, radio mast). Individuals with WS performed better than a matched subset of TD children on more difficult routes; we suggest that this is supported by relatively strong visual feature recognition in the disorder. Participants with DS who had relatively high levels of non‐verbal ability performed at a similar level to TD participants.     

Lay people's and police officers' attitudes towards the usefulness of perpetrator voice identification

Expert and lay knowledge of factors that affect the identification of a voice is an area of research that is still relatively unexplored. Much more research has focused on eyewitness identification and eyewitnesses' common knowledge. However, results from ‘eyewitnessing’ studies may not be directly applicable to ‘earwitnessing’. The present study examines how knowledgeable British lay people and police officers were concerning earwitness identification performance. One hundred nine participants (i.e. 49 lay people and 60 police officers) responded to a specially designed questionnaire. Results showed respondents to be more knowledgeable than expected, although police officers were no more knowledgeable than the general population. The existence of meta‐knowledge is discussed in relation to previous studies. Copyright © 2006 John Wiley & Sons, Ltd.     

Earwitness identification performance: the effect of language,target, deliberate strategies and indirect measures

The present study examined whether voice identification performance is influenced by language comprehension (i.e. familiar vs. non‐familiar language) and target presence (target‐present (TP) vs. target‐absent line‐ups (TA)). It also looked at the relationship of deliberate strategies and indirect measures (i.e. confidence, difficulty and pressure) with performance. Sixty Native English speakers were exposed to an auditory event involving 45 to 50 seconds of speech. After 30 minutes delay, participants listened to a voice line‐up (TP or TA) in either a familiar (i.e. English) or unfamiliar language (i.e. French) according to the language spoken during the event, and were then asked to identify the original speaker's voice. Participants demonstrated significantly better performance for the familiar language/TP line‐ups. Participants who reported using the ‘elimination’ strategy were significantly more accurate than participants who reported using either a ‘matching’ strategy or no strategy. Indirect measures were not found to be good predictors of performance, except for confidence regarding TA accuracy. Copyright © 2006 John Wiley & Sons, Ltd.     

Peripheral and central contribution to the difficulty of speech in noise perception in dyslexic children

Noise typically induces both peripheral and central masking of an auditory target. Whereas the idea that a deficit of speech in noise perception is inherent to dyslexia is still debated, most studies have actually focused on the peripheral contribution to the dyslexics’ difficulties of perceiving speech in noise. Here, we investigated the respective contribution of both peripheral and central noise in three groups of children: dyslexic, chronological age matched controls (CA), and reading‐level matched controls (RL). In all noise conditions, dyslexics displayed significantly lower performance than CA controls. However, they performed similarly or even better than RL controls. Scrutinizing individual profiles failed to reveal a strong consistency in the speech perception difficulties experienced across all noise conditions, or across noise conditions and reading‐related performances. Taken together, our results thus suggest that both peripheral and central interference contribute to the poorer speech in noise perception of dyslexic children, but that this difficulty is not a core deficit inherent to dyslexia.