Biology subjects

Weiss, P. H.

Publications and source records attributed to Weiss, P. H..

5 recordsLinked to original sources

bioRxiv2022

Crossmodal reorganization in deaf auditory cortices compensates for the impaired body-centered visuomotor transformation after early deafness

Early deafness leads to the reorganization of large-scale brain networks, involving and extending beyond the auditory system. Body-centered visuomotor transformation is impaired after early auditory deprivation, associated with a hyper-crosstalk between the task-critical frontoparietal network (FPN) and the default-mode network (DMN). It remains to be elucidated, how the reorganized functional connectivity between the auditory system, the FPN, and the DMN contributes to the impaired visuomotor transformation after early deafness. In this fMRI study, we asked early deaf participants and hearing controls to judge the spatial location of a visual target, either about the middle-sagittal line of their own body (the egocentric task) or another background object (the allocentric task). The bilateral superior temporal gyrus (STG) in the deaf group exhibited cross-modal reorganization, with generally enhanced neural activity during the visual tasks, compared to hearing controls. Moreover, the STG showed significantly increased functional connectivity with both the FPN and the DMN in the deaf group compared to hearing controls, specifically during the egocentric task. The increased STG-FPN and STG-DMN coupling, however, showed antagonistic effects on the egocentric performance of the deaf participants. The increased STG-FPN connectivity was associated with improved (i.e., a beneficial role) while the increased STG-DMN with deteriorated (i.e., a detrimental role) egocentric performance in the deaf participants. No such effect was observed in hearing controls. Therefore, the auditory cortex is reorganized to functionally resemble the FPN in the deaf brain, representing compensatory neuroplasticity to mitigate the impaired visuomotor transformation after early deafness. Significance StatementOur brain constantly plans vision-guided actions, transforming visuospatial representations of external visual targets into visuomotor representations. The frontoparietal network (FPN) critically supports this visuomotor transformation process, which is impaired after early deafness. To mitigate the impaired visuomotor transformation, the deaf auditory cortex in the bilateral superior temporal gyrus (STG) shows compensatory cross-modal reorganization that functionally resembles the FPN regions. Specifically, the deaf auditory cortex becomes functionally coupled with the dorsal FPN regions. The stronger the STG-FPN coupling, the more improved the deaf adults visuomotor transformation performance, indicating the reorganized STG as a critical node of the task-critical network. Correspondingly, increased coupling between the task-critical deaf STG and the default-mode network impairs the visuomotor transformation.

neuroscience↗

bioRxiv2022

The relationship between response dynamics and the formation of confidence varies across the lifespan

Accurate metacognitive judgements, such as forming a confidence judgement, are crucial for goaldirected behaviour but decline with older age. Besides changes in the sensory processing of stimulus features, there might also be changes in the motoric aspects of giving responses that account for age-related changes in confidence. In order to assess the association between confidence and response parameters across the adult lifespan, we measured response times and peak forces in a four-choice flanker task with subsequent confidence judgements. In 65 healthy adults from 20 to 76 years of age, we showed divergent associations of each measure with confidence, depending on decision accuracy. Participants indicated higher confidence after faster responses in correct but not incorrect trials. They also indicated higher confidence after less forceful responses in errors but not in correct trials. Notably, these associations were age-dependent as the relationship between confidence and response time was more pronounced in older participants, while the relationship between confidence and response force decayed with age. Our results add to the notion that confidence is related to response parameters and demonstrate noteworthy changes in the observed associations across the adult lifespan. These changes potentially constitute an expression of general age-related deficits in performance monitoring or, alternatively, index a failing mechanism in the computation of confidence in older adults.

neuroscience↗

bioRxiv2022

Speeded Inference Game: Opening a new chapter in the assessment of error awareness

Influential theories on error processing assume that when we conduct errors adaptive processes are triggered to improve our behaviour and prevent errors in the future. These processes appear to be more effective after participants have detected an error. Therefore, the assessment of error awareness allowing a differential analysis of detected and undetected errors in the context of cognitive control and behavioural adjustments has gained more and more attention in the past decades. A common methodological challenge posed on all studies investigating error detection is that the number of undetected errors is usually relatively low. Here, we introduce a gamified experimental task that uses an adaptive algorithm to generate a robust and stable amount of errors with a high rate of undetected errors. Further, we were able to identify error types, which interestingly differed in terms of their detection rate. Moreover, the game-like appearance of the novel experimental task led to highly motivated participants. The results of the first study were replicated and extended by a second behavioural study. Notably, in study 2, a change in task design specifically modulated error detection, while these changes did not affect the total error rate. Potential applications of the open-source code will be discussed. With this newly developed paradigm, we wish to lay the ground for future research to understand better (neural) processes associated with error awareness.

neuroscience↗

bioRxiv2021

Divergent effects of absolute evidence magnitude on decision accuracy and confidence in perceptual judgements

Whether people change their mind after making a perceptual judgement may depend on how confident they are in their decision. Recently, it was shown that, when making perceptual judgements about stimuli containing high levels of absolute evidence (i.e., the overall magnitude of sensory evidence across choice options), people make less accurate decisions and are also slower to change their mind and correct their mistakes. Here we report two studies that investigated whether high levels of absolute evidence also lead to increased decision confidence. We used a luminance judgment task in which participants decided which of two dynamic, flickering stimuli was brighter. After making a decision, participants rated their confidence. We manipulated relative evidence (i.e., the mean luminance difference between the two stimuli) and absolute evidence (i.e., the summed luminance of the two stimuli). In the first experiment, we found that higher absolute evidence was associated with decreased decision accuracy but increased decision confidence. In the second experiment, we additionally manipulated the degree of luminance variability to assess whether the observed effects were due to differences in perceived evidence variability. We replicated the results of the first experiment but did not find substantial effects of luminance variability on confidence ratings. Our findings support the view that decisions and confidence judgments are based on partly dissociable sources of information, and suggest that decisions initially made with higher confidence may be more resistant to subsequent changes of mind.

neuroscience↗

bioRxiv2021

Neural correlates of metacognition across the adult lifespan

Metacognitive accuracy describes the degree of overlap between the subjective perception of ones decision accuracy (i.e., confidence) and objectively observed performance. With older age, the need for accurate metacognitive evaluation increases; however, error detection rates typically decrease. We investigated the effect of ageing on metacognitive accuracy using event-related potentials (ERPs) reflecting error detection and confidence: the error/correct negativity (Ne/c) and the error/correct positivity (Pe/c). Sixty-five healthy adults (20 to 76 years) completed a complex perceptual task and provided confidence ratings. We found that metacognitive accuracy declined with age beyond the expected decline in task performance, while the adaptive adjustment of behaviour was well preserved. Pe/c amplitudes varied by confidence rating, but they did not mirror the reduction in metacognitive accuracy. Ne/c amplitudes decreased with age except for high confidence correct responses. The results suggest that age-related difficulties in metacognitive evaluation could be related to an impaired integration of decision accuracy and confidence information processing. Ultimately, training the metacognitive evaluation of fundamental decisions in older adults might constitute a promising endeavour.

neuroscience↗