Poster A63, Saturday, March 25, 5:00 – 7:00 pm, Pacific Concourse
Verbal labelling of tactile percepts increases connectivity between somatosensory and auditory cortices
Tally McCormick Miller1,3, Timo Torsten Schmidt2,4, Felix Blankenburg2,3, Friedemann Pulvermüller1,3; 1Brain Language Laboratory, Freie Universität Berlin, 2Neurocomputation and Neuroimaging Unit, Freie Universität Berlin, 3Berlin School of Mind and Brain, Humboldt Universität Berlin, 4Institute of Cognitive Science, Universität Osnabrück, Germany
In its strong form, the linguistic relativity (‘Whorfian’) hypothesis claims that language structure has a causal effect on perception. To date, the majority of research relies heavily on natural languages and between-group comparisons to determine whether differences in vocabulary may lead to differences in perception. To determine whether labels could facilitate tactile perception, we used complex vibroractile patterned stimuli. To avoid natural language confounds while studying within-subject manipulation, these patterns were simultaneously presented with pseudowords during a week-long intense association phase. To test whether consistently pairing a percept (vibrotactile pattern) and a pseudoword could influence perceptual abilities, one set of pseudowords was assigned to one set of vibrotactile patterns and these were consistently paired during association. A second set was randomly paired as a control condition. After one week of associative training, subjects demonstrated discrimination improvement only for concordantly labeled vibrotactile stimuli. fMRI data were collected after this association phase. To assess corresponding changes in the interaction of auditory and somatosensory cortical networks, we used psychophysiological interaction analyses (PPI). We tested for differences in functional connectivity between auditory and primary/secondary somatosensory cortex when pseudowords from the concordant condition were presented, in comparison to pseudowords from the control condition. This analysis revealed increased bilateral coupling between primary auditory and secondary somatosensory cortex for concordantly labelled stimuli. This suggests a rapid formation of an integrated network via Hebbian associative learning, and that consistently pairing a verbal label with a percept may potentially enable one to better distinguish this percept amongst similar percepts.
Topic Area: LANGUAGE: Semantic