Neural representations of haptic object size in the human brain revealed by multivoxel fMRI patterns

Abstract

Our understanding of the neural basis of haptics (perceiving the world through touch) remains incomplete. We used functional MRI to study human haptic judgments of object size, which require integrating multiple afferent signals. Multivoxel pattern analyses identified intraparietal and prefrontal regions that encode size haptically in a metric and hand-invariant fashion. Effector-independent haptic size estimates are useful on their own and in combination with other sensory estimates for a variety of perceptual and motor tasks.

Decoding grasp and speech signals from the cortical grasp circuit in a tetraplegic human

“…Study of the underlying feature space in SMG's neuronal population suggested that hand posture (proximity of ''lateral'' and ''palmar pinch'' in principal component analysis (PCA) space, Figure S2C) rather than object size and shape modulate SMG activity. These results support fMRI findings, where object size was not shown to modulate SMG activity (Perini et al, 2020).…”

Aging and the visual perception of object size

“…In this context, it is quite interesting to find in the current study that there was no age-related degradation in either the accuracy or precision of our observers' judgments of object size. Given that the visual perception of object size depends upon such areas as the lateral occipital (LO) cortex 29 , posterior parietal cortex 30 , the intraparietal sulcus and lateral prefrontal cortex 31 , our current behavioral findings suggest that there is little or no degradation in intracortical inhibitory functionality within these areas. It…”

IL-6-induced upregulation of T-type Ca2+ currents and sensitization of DRG nociceptors is attenuated by MNK inhibition: translational research perspective

“…TO THE EDITOR: Nociceptor hyperexcitability is emerging as a major public health challenge globally; precise dissection of cellular, molecular, and genetic regulatory networks is essential for demystifying the underlying neurophysiological basis of IL-6-induced upregulation of T-type Ca 2ϩ currents and sensitization of dorsal root ganglions (DRG) nociceptors in "at risk" susceptible populations of varying genetic and metabolic profiles (Black et al 1999;Jeevakumar et al 2020;Perini et al 2020). The study by Jeevakumar et al (2020) entitled "IL-6induced upregulation of T-type Ca 2ϩ currents and sensitization of DRG nociceptors is attenuated by MNK inhibition" published in Journal of Neurophysiology is indeed enlightening.…”