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Maruo, K.

Publications and source records attributed to Maruo, K..

2 recordsLinked to original sources

Representational similarity of hemodynamic brain responses to written and spoken words increases when learning to read

Learning to read requires binding auditory and visual information together, yet how the developing brain maps information across sensory modalities remains poorly understood. To shed light on this topic we employed functional magnetic resonance imaging to investigate hemodynamic brain responses during spoken and written word or pseudoword recognition in primary school children with different levels of reading experience. Audiovisual representational similarity of activation patterns in the inferior frontal gyrus, inferior parietal lobule, superior temporal gyrus, and temporo-occipital cortex, increased with school grade and this similarity was largest in the left posterior superior temporal gyrus. Our results suggest that learning to read is related to increasing neurophysiological similarity of auditory and visual word representations within canonical language areas.

neuroscience↗

Lid speculum as effective active and reference electrodes for electroretinography recording in normal rabbits

PurposeAlthough electroretinography (ERG) is vital for evaluating retinal function, conventional corneal electrodes slide or detach in animals. This study aimed to investigate the effectiveness of a novel approach to ERG recording using a metal eyelid speculum for both active and reference electrodes in conjunction with a skin electrode-based ERG device. MethodsWe tested a stainless-steel eyelid speculum as both active and reference electrodes with a skin-electrode ERG system (HE-2000vet) in six healthy Japanese White rabbits. Dark-adapted rod and maximal responses and light-adapted cone and 30 Hz flicker ERGs were recorded in three weekly sessions. ResultsReproducible waveforms with identifiable a- and b-waves were obtained in every eye; rod b-waves reached 50-90 {micro}V and cone b-waves 40-55 {micro}V. Intraclass correlation coefficients revealed substantial interocular agreement and moderate-to-substantial inter-session reproducibility for b-wave amplitude and implicit time, whereas a-wave metrics were less reliable owing to lower amplitudes. The advantages of speculum electrode over corneal electrodes are that it requires no fur shaving, maintains stable contact regardless of globe orientation, and allows real-time observation. ConclusionsThis study demonstrated that an eyelid-speculum electrode is a practical, non-invasive alternative for veterinary and experimental ERG recordings, producing signal quality sufficient for longitudinal and interocular analyses while avoiding cosmetic and technical drawbacks of conventional methods.

neuroscience↗