Increased visual sensitivity and occipital activity in patients with hemianopia following vision rehabilitation

Acknowledgements We would like to thank the participants for giving up their time to engage with the research.Peer reviewedPublisher PD

The sensitivity and specificity of a diagnostic test of sequence-space synesthesia

People with sequence-space synaesthesia (SSS) report stable visuo-spatial forms corresponding to numbers, days and months (amongst others). This type of synaesthesia has intrigued scientists for over 130 years but the lack of an agreed upon tool for assessing it has held back research on this phenomenon. The present study builds on previous tests by measuring the consistency of spatial locations that is known to discriminate controls from synaesthetes. We document, for the first time, the sensitivity and specificity of such a test and suggest a diagnostic cut-off point for discriminating between the groups based on the area bounded by different placement attempts with the same item

The rubber hand illusion depends on the tactile congruency of the observed and felt touch.

The rubber hand illusion (RHI) occurs when the participants' own unseen hand is stroked in synchrony with an observed rubber hand. It manifests itself in terms of a tendency to misreport the position of one's own hand as nearer to the rubber hand (proprioceptive drift) and in terms of feelings of ownership of the rubber hand. Many studies have examined whether the illusion depends on characteristics of the hand (e.g., orientation, skin color), but very few have examined the importance of the tool that delivers the tactile sensation. We demonstrate that the RHI depends on the congruency of the tool used to stroke the real/rubber hands. The RHI is diminished when using tools that are incongruent with respect to their visual appearance and predicted tactile consequences (e.g., touching the dummy with a pencil and the real hand with a paintbrush) relative to when they are congruent. Theoretical models of visuotactile integration used to explain the RHI need to be extended to incorporate the qualitative nature of the observed and felt touch and not just its synchrony and location. (PsycINFO Database Recor

Natural visual behavior in individuals with peripheral visual-field loss

Retinitis pigmentosa (RP) is an inherited disease that causes progressive peripheral visual-field loss. In this study, we investigated how such loss affects visual exploration of natural images. Individuals with varying degrees of visual-field loss and healthy control participants freely observed images of different sizes while eye movements were recorded. We examined whether visual behavior differed when the scene content was shown in various extents of the visual field, and investigated the spatial bias, saccade amplitudes, and number and duration of fixations. We found that the healthy control group showed a central spatial bias during image viewing. The RP group showed similar biases on the group level, but with reproducible individual exploration patterns. For saccade amplitudes, the healthy control group and the RP group showed similar behavior throughout all image sizes. The RP group with severe loss of peripheral vision thus tended to target saccades toward blind areas of their visual field. The number of fixations did not change between the two groups, although fixation durations decreased in the RP group. In conclusion, the RP group scanned the images surprisingly similarly to the healthy control group; however, they showed individual idiosyncratic explorative strategies when the observed scene exceeded their visible field. Thus, although RP leads to a severe loss of the visual field, there is no general adaptive mechanism to change visual exploration. Instead, individuals rely on individual strategies, leading to high heterogeneity in the RP group

Fine motor control improves in older adults after one year of piano lessons ::analysis of individual development and its coupling with cognition and brain structure

Musical training can improve fine motor skills, cognitive abilities and induce macrostructural brain changes. However, it is not clear whether the changes in motor skills occur simultaneously with changes in cognitive and neurophysiological parameters. In this study, 156 healthy, musically naïve, and right-handed older adults were recruited and randomly assigned to a piano training or a music listening group. Before, after six and twelve months participants were scanned using MRI and assessed for fine motor skills, auditory working memory and processing speed. A Bayesian multilevel modeling approach was used to examine behavioral and neurophysiological group differences. The relationships between motor and cognitive and between motor and neurophysiological parameters were determined using latent change score models. Compared to music listening, practicing piano resulted in greater improvement in fine motor skills and probably working memory. Only in the piano group, unimanual fine motor skills and gray matter volume of the contralateral M1 changed together during the 6–12-month period. Additionally, M1 co-developed with ipsilateral putamen and thalamus. Playing piano induced more prevalent coupling between the motor and cognitive domain. However, there is little evidence that fine motor control develops concurrently with cognitive functions. Playing an instrument promotes motor, cognitive and neural development into older age. During the learning process, the consolidation of piano skills appears to take place in sensorimotor networks, enabling musicians to perform untrained motor tasks with higher acuity. Relationships between the development of motor acuity and cognition were bidirectional and can be explained by a common cause as well as by shared resources with compensatory mechanisms

Improved speech in noise perception in the elderly after six months of musical instruction

Understanding speech in background noise poses a challenge in daily communication, which is a particular problem among the elderly. Although musical expertise has often been suggested to be a contributor of speech intelligibility, the associations are mostly correlative. In the present multisite study conducted in Germany and Switzerland, 156 healthy, normal-hearing elderly were randomly assigned to either piano playing or physically music listening/musical culture groups. The speech reception threshold was assessed using the International Matrix Test before and after a six months intervention. Bayesian multilevel modeling revealed an improvement of both groups over time under binaural conditions. Additionally, the speech reception threshold of the piano group decreased during stimuli presentation to the left ear. A right ear improvement only occurred in the German piano group. Furthermore, improvements were predominantly found in women. These findings are discussed in the light of current neuroscientific theories on hemispheric lateralization and biological sex differences. The study indicates a positive transfer from musical training to speech processing, probably supported by the enhancement of auditory processing and improvement of general cognitive functions

Evidence of cortical thickness increases in bilateral auditory brain structures following piano learning in older adults

Morphological differences in the auditory brain of musicians compared to nonmusicians are often associated with life-long musical activity. Cross-sectional studies, however, do not allow for any causal inferences, and most experimental studies testing music-driven adaptations investigated children. Although the importance of the age at which musical training begins is widely recognized to impact neuroplasticity, there have been few longitudinal studies examining music-related changes in the brains of older adults. Using magnetic resonance imaging, we measured cortical thickness (CT) of 12 auditory-related regions of interest before and after 6 months of musical instruction in 134 healthy, right-handed, normal-hearing, musically-naive older adults (64–76 years old). Prior to the study, all participants were randomly assigned to either piano training or to a musical culture/music listening group. In five regions—left Heschl's gyrus, left planum polare, bilateral superior temporal sulcus, and right Heschl's sulcus—we found an increase in CT in the piano training group compared with the musical culture group. Furthermore, CT of the right Heschl's gyrus could be identified as a morphological substrate supporting speech in noise perception. The results support the conclusion that playing an instrument is an effective stimulator for cortical plasticity, even in older adults