|Description||Schröder, P., Schmidt, T. T., & Blankenburg, F. (2019). Neural basis of somatosensory target detection independent of uncertainty, relevance, and reports. eLife, 8, e43410. https://doi.org/10.7554/eLife.43410.001
Abstract: Research on somatosensory awareness has yielded highly diverse findings with putative neural correlates ranging from activity within somatosensory cortex to activation of widely distributed frontoparietal networks. Divergent results from previous studies may reside in cognitive processes that often coincide with stimulus awareness in experimental settings. To scrutinise the specific relevance of regions implied in the target detection network, we used functional magnetic resonance imaging (n = 27) on a novel somatosensory detection task that explicitly controls for stimulus uncertainty, behavioural relevance, overt reports, and motor responses. Using Bayesian Model Selection, we show that responses reflecting target detection are restricted to secondary somatosensory cortex, whereas activity in insular, cingulate, and motor regions is best explained in terms of stimulus uncertainty and overt reports. Our results emphasise the role of sensory-specific cortex for the emergence of perceptual awareness and dissect the contribution of the frontoparietal network to classical detection tasks.
Comments: Exceedance probability maps for GLMs modelling physical stimulus intensity, target detection, detection probability, uncertainty, and reports are provided. Another exceedance probability map is provided for a model family ("+family") consisting of the intensity, detection, and detection probability models, which was used to define ROIs. All maps are unthresholded. For statistical inference, the +family, uncertainty, and report models were assessed at a threshold of EP >= .99. The intensity, detection, and detection probability models were assessed within the +family ROIs only (which is why only a subset of voxels is shown) and they were not further thresholded. |