Action–perception coupling in kinesthesia: A new approach

• Published in: Neuropsychologia 2013-11, Vol.51 (13), p.2590-2599
• Main Authors: Feldman, Anatol G., Ilmane, Nabil, Sangani, Samir, Raptis, Helli, Esmailzadeh, Nima
• Format: Article
• Language: English
• Subjects: Adult; Adult and adolescent clinical studies; Afferent feedback; Analysis of Variance; Biological and medical sciences; Body scheme; Elbow - innervation; Electromyography; Female; Humans; Intention; Kinesthesis - physiology; Kinesthetic illusions; Male; Medical sciences; Motion; Nervous system (semeiology, syndromes); Nervous system as a whole; Neurology; Organic mental disorders. Neuropsychology; Perception - physiology; Phantom limb; Physical Stimulation; Position sense; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Referent body configuration; Sense of effort; Tendons - innervation; Vibration; Wrist Joint - innervation; Young Adult
• ISSN: 0028-3932; 1873-3514
• DOI: 10.1016/j.neuropsychologia.2013.09.013

According to recent findings, intentional motor actions are controlled by resetting the referent position, R, at which neuromuscular elements, including reflexes, begin to act. It is suggested that somatosensory afferents inform the brain about the deviation (P) of body segments from the centrally set referent position. To perceive the actual position (Q) of body segments and form the position sense (PS), the central and afferent signals are combined: Q=R+P. In previous studies, the R has been shown to remain invariant during involuntary changes in the wrist position elicited by sudden unloading of muscles, suggesting that only the afferent component is responsible for the PS during this reflex. In contrast, the central PS component, R, is predominantly responsible for PS during intentional motion in isotonic conditions. We tested the hypothesis that the R and P are interchangeable PS components such that involuntary changes in wrist position elicited by the unloading reflex can easily be reproduced by making intentional changes in wrist position in isotonic conditions, in the absence of vision. The PS rule also suggests that PS is independent of sense of effort, which was tested by asking subjects to reproduce elbow joint angles under different constant loads. We also tested the hypothesis that tendon vibration may elicit motion that may not be perceived by subjects (no-motion illusion). These hypotheses were confirmed in three experiments. It is concluded that the R and P are additive components of PS and that, contrary to the conventional view, PS is independent of the sense of effort or efference copy. The PS rule also explains kinesthetic illusions and the phantom limb phenomenon. This study advances the understanding of action–perception coupling in kinesthesia. •Afferent signals detect deviations of body segments from the referent posture.•Position sense is based on the central referent and peripheral afferent inputs.•Results reject the notion that position sense depends on efference copy or sense of effort.•The approach helps explain position sense in different motor tasks and the phantom limb phenomenon.