Servicenavigation

Project Details

Back

Projekt Print View

Local tactile coding in the human fingertip

Subject Area Cognitive, Systems and Behavioural Neurobiology
Term from 2016 to 2024
Project identifier Deutsche Forschungsgemeinschaft (DFG) - Project number 280069124
 
Final Report Year 2024

Final Report Abstract

In this project we studied a novel hypothesis about tactile sensing and perception that we established based on previous work in the rat whisker-related tactile system, transferring it to the human tactile fingertip system. Based on our finding that frictional movements, consisting on short-lasting stick-slip movements, carry texture information, we hypothesized that the tactile system, rather than averaging across the vibrotactile signal to calculate ‘intensity’ and ‘best frequency’, performs event-detection and -extraction, followed by waveform analysis used to be able to infer instantaneously about the identity of a touched tactile object (texture). In the course of application for the renewal the corona pandemic hit and stopped the planned experimental work on human participants for more than a year. With the loss of time during the pandemic, we decided to focus the project fully on psychophysics and combine it with MEG/EEG recording. In the end of the funding period we were able to start the study of sensorimotor interactions. We established three novel behavioural paradigms and established their combination with MEG/EEG recordings. We were able to confirm findings from our rodent work in humans. Humans were shown to be able to discriminate kinematic pulse shapes while they have great difficulty to use pulse rate (of identical pulses). As these findings break with long-standing tradition in thinking about tactile processing, it received great attention and surprise, and sometimes resistance, in the field of primate tactile perception. Given the dominant paradigms of ‘intensity’ and ‘frequency’ coding this result laid outside main stream thinking only a few years ago. We started combining human psychophysics with EEG recordings, investigating S1 activity in response to isolated short indentation pulses. Preliminary results showed a tendency (matching our previous results in rodents) that local coding has reflections in activity that likely is located in primary somatosensory cortex. Finally, using MEG recordings we studied an important precondition to study temporally local coding, the effect of movement on tactile flow called sensory gating. We found that a tactile stimulus bound to movement in terms of a contingent cue-response pair is not prone to sensory gating.

Publications

 
 

Additional Information

© 2026 DFG Disclaimer / Copyright / Privacy Policy

Textvergrößerung und Kontrastanpassung