Comparison of brain activity during different types of proprioceptive inputs: a positron emission tomography study

Abstract

It has been shown that the primary and secondary somatosensory cortex, as well as the supplementary motor area (SMA), are involved in central processing of proprioceptive signals during passive and active arm movements. However, it is not clear whether different cortical areas are involved in processing of different proprioceptive inputs (skin, joint, muscle receptors), what their relative contributions might be, where kinesthetic sensations are formed within the CNS, and how they interact when the full peripheral proprioceptive machinery acts. In this study we investigated the representation of the brain structures involved in the perception of passive limb movement and illusory movement generated by muscle tendon vibration. Changes in cortical activity as indicated by changes in regional cerebral blood flow (rCBF) were measured using positron emission tomography (PET). Twelve subjects were studied under four conditions: (1) passive flexion-extension movement (PM) of the left forearm; (2) induced illusions of movements (VI) similar to the real PM, induced by alternating vibration of biceps and triceps tendons (70-80 Hz) at the elbow; (3) alternating vibration of biceps and triceps tendons (with 20-50 Hz) without induced kinesthetic illusions (VN); and (4) rest condition (RE). The results show different patterns of cortex activation. In general, the activation during passive movement was higher in comparison with both kinds of vibration, and activation during vibrations with induced illusions of movement was more prominent than during vibrations without induced illusions. When the PM condition was contrasted with the other conditions we found the following areas of activation -- the primary motor (MI) and somatosensory area (SI), the SMA and the supplementary somatosensory area (SSA). In conditions where passive movements and illusory movements were contrasted with rest, some temporal areas, namely primary and associative auditory cortex, were activated, as well as secondary somatosensory cortex (SII). Our data show that different proprioceptive inputs, which induce sensation of movement, are associated with differently located activation patterns in the SI/MI and SMA areas of the cortex. In general, the comparison of activation intensities under different functional conditions indicates the involvement of SII in stimulus perception generation and of the SI/MI and SMA areas in the processing of proprioceptive input. Activation of the primary and secondary auditory cortex might reflect the interaction between somatosensory and auditory systems in movement sense generation. SSA might also be involved in movement sense generation and/or maintenance.

Short-term learning of a visually guided power-grip task is associated with dynamic changes in EEG oscillatory activity

“…Among other functions, the SMA seems to be involved in movement control ( [Cunnington et al, 2002], [Floyer-Lea and Matthews, 2004], [Stephan et al, 1995] and [Vaillancourt et al, 2003]) which would support the idea of ERS reflecting a reset of cortical activity in brain regions involved in a motor task as expressed in the 'idling' hypothesis . On the other hand, the SMA receives proprioceptive input from sensory afferents stimulated by passive movements (Radovanovic et al, 2002), supporting the reafferent input hypothesis of ERS ( [Cassim et al, 2001] and [Labyt et al, 2003]). Another medial frontal structure, the anterior cingulate cortex (ACC), has been suggested to have a fundamental role in relating actions to their consequences (Rushworth et al, 2004).…”

Cerebral cortical representation of external anal sphincter contraction: effect of effort

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Novel magnetomechanical MR compatible vibrational device for producing kinesthetic illusion during fMRI

“…15,25,26 At a slightly lower threshold of P ≤ 0.1 (FWE) revealed a contralateral cluster of activation in S1 further supporting the stimulation of the sensorimotor network by the kinesthetic illusion. Although our protocol of continuous stimulation was unusual the stimulus changed regularly between the high illusion inducing frequencies and the low sensory frequencies so the muscle spindles endings were not constantly producing movement signals.…”