The European journal of neuroscience
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Sounds of hammering or clapping can evoke simulation of the arm movements that have been previously associated with those sounds. This audio-motor transformation also occurs at the sequential level and plays a role in speech and music processing. The present study aimed to demonstrate how the activation pattern of the sensorimotor network was modulated by the sequential nature of the auditory input and effector. ⋯ These regions might mediate the one-to-one mappings from sounds to limb movements. Compared with subvocal rehearsals along with learned drum music, covert rehearsals of limb movements along with the same music additionally activated a lateral subregion of the left posterior planum temporale. Our results illustrate a functional specialization of the posterior temporal lobes for audio-motor processing.
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The present study aimed to create a direct bridge between observations on peripheral and central responses to odorant mixtures and their components. Three experiments were performed using mixtures of fruity (isoamyl acetate; ISO) and woody (whiskey lactone; WL) odorants known to contribute to some of the major notes in Burgundy red wine. These experiments consisted of (i) calcium imaging of human embryonic kidney cells (HEK293T) transfected with olfactory receptors (ORs); (ii) single-unit electrophysiological recordings from olfactory receptor neurons (ORNs) and analyses of electro-olfactogram (EOG) responses in the rat nose in vivo; and (iii) psychophysical measurements of the perceived intensity of the mixtures as rated by human subjects. ⋯ In the human studies, the addition of high concentrations of WL to ISO decreased the perceived intensity of the ISO. In contrast, the addition of low concentrations of WL enhanced the perceived intensity of the fruity note (ISO) in this mixture, as it enhanced EOG responses in ORNs. Thus, both OR and ORN responses to ISO + WL mixtures faithfully reflected perceptual response changes, so the odour mixture information is set up after the peripheral stage of the olfactory system.