Neuropsychologia最新文献

A long-standing controversial issue in speech perception concerns the automatic nature of audiovisual speech integration, independent of attentional and cognitive load. From this question, the present EEG study aimed to determine whether visual load and associated task difficulty can modulate audiovisual speech integration and, if so, at what stage of neural processing. To this end, four syllable discrimination tasks differing in the degree of visual discrimination and speaker variability were performed in auditory, visual, and audiovisual modalities. Early and late effects of audiovisual integration, as well as late effects of visual load, were observed on auditory evoked responses. Crucially, the neural binding of acoustic and visual speech signals was not modulated by either visual discrimination or speaker variability. These results support an automatic integration of acoustic and visual speech cues, independent of visual load, during audiovisual syllable discrimination.

In the last decade, studies have indicated an association between Visual-Spatial Working Memory (VSWM) domain-general cognitive ability, and number processing. We aimed to further elaborate this relationship in adults behaviorally and neuro-cognitively via fMRI. Fifty one student were recruited from them forty students were included in the analysis (males, N=23; females, N=17). Based on an outside scanner VSWM task, the participants were divided into High and Low VSWM Groups. During an fMRI scan, participants performed a Number line estimation task. Data were analyzed at the individual-participant level and at the group level. Multiple comparisons between the groups were carried out on the whole brain level and at specific ROIs (Regions of Interest). Behavioral results showed that the Low VSWM Group exhibited longer reaction time as compared with the High VSWM Group, in symbolic numerical processing. Neuroanatomical comparisons revealed greater activation mainly in right fronto-parietal regions among the High VSWM Group during the Number line estimation task, while the Low VSWM group engaged the left hemisphere, in parietal, frontal and temporal regions. ROI analyses showed that the left IPS activation was positively correlated to the Number line Task, thus indicating its specific role in symbolic number processing. These results demonstrate hemispherical differences between the groups during number processing, suggesting that people with High VSWM recruit resources from a domain-general ability (VSWM) which enables them to process symbolic numbers more efficiently, while people with Low VSWM capacity rely more on verbal abilities to compensate for lower spatial abilities when processing symbolic numerals.

Individuals differ in both their navigation abilities and preferences. As children age, their spatial abilities develop, which allows for an increase in the use of survey knowledge to support navigation along novel routes or with shortcuts. Gender differences in navigation also emerge from preadolescence to adolescence, corresponding to changes in hormones and experience. The current study aimed to examine differences in navigation strategy in individuals aged 8-40. Participants completed the dual solution paradigm (DSP) where they learned a virtual environment with a layout of unique objects and were then tested on their ability to navigate back to those objects. We measured average time to complete trials, success, and strategies to take learned or novel routes to better understand the differences in spatial knowledge and strategy preference across a wide age range. We also grouped our child population (ages 8-12, 13-17) and performed additional analyses to examine the impact puberty has on these measures. The results showed that male participants navigated more efficiently and had higher rates of success than female participants, overall. For male participants, as age increased, average time to complete trials decreased. The categorical analyses showed gender differences in success and time in adolescents but not preadolescents. There were no age or gender differences in strategy usage. Our results suggest that certain spatial abilities develop at different ages depending on gender and that by adolescence children are performing at adult levels when tasked with navigating efficiently in a maze environment. These findings allow us to better understand how gender differences in navigation develop before and after the onset of puberty.