Motor imagery practice may compensate for the slowdown of sensorimotor processes induced by short-term upper-limb immobilization

Abstract

Recently, it has been demonstrated that sensorimotor representations are quickly updated following a brief period of limb non-use. The present study examined the potential of motor imagery practice (MIP) and investigated the role of motor imagery instructions (kinesthetic vs. visual imagery) to counteract the functional impairment induced by sensorimotor restriction. The participants were divided into four groups. Three groups wore a splint on their left hand for 24 h. Prior to the splint removal, two of the three groups performed 15 min of MIP, with kinesthetic or visual modalities (KinMIP and VisMIP groups, respectively). The third group did not practice motor imagery (NoMIP group). Immediately after the splint removal, the participants were assessed using a hand laterality task known for evaluating sensorimotor processes. A fourth group served as the control (i.e., without immobilization and MIP). The main results showed slower left-hand response times for the immobilized NoMIP group compared with the controls. Importantly, faster response times for the left-hand stimuli appeared for the KinMIP groups only compared with the NoMIP group. No difference between the four groups was observed for the right-hand stimuli. Overall, these results highlighted the somatotopic effect of limb non-use on the efficiency of sensorimotor processes. Importantly, the slowdown of the sensorimotor processes induced by 24 h of sensorimotor deprivation may be counteracted by a kinesthetic MIP, whereas no beneficial effect appeared with visual imagery. We discuss the importance of imagery modalities for sensorimotor reactivation.

Motor imagery practice during arm-immobilization benefits sensorimotor cortical functions and plasticity-related sleep features

“…The lack of task-repetition benefit after the NoMI condition for both right and left hand stimuli confirms and extends previous findings by Toussaint et al [23] obtained after 48h of nondominant hand immobilization. Performance gains observed following the MI condition further support previous data showing that 15 min of kinesthetic MI performed right before splint removal following 24 hr of left hand immobilization, contributed to improve the response time to identify left hand stimuli [14]. Based on this result, kinesthetic MI was thought to reactivate proprioceptive and motor processing, counteracting the effects of immobilization.…”

“…These authors suggested that the peripheral alteration affected the sensorimotor representation of the hand, which became less effective or more difficult to stress. Performance gains observed following the ImMI condition further support previous data showing that 15 min of kinesthetic MI performed right before splint removal following 24 hr of left hand immobilization, contributed to improve the response time to identify left hand stimuli [14]. Based on this result, kinesthetic MI was thought to reactivate proprioceptive and motor processing to their initial level of functioning.…”

“…In case of upper limb immobilization, however, contrasting results on MI efficiency have been reported, hence precluding from drawing general conclusions. Interestingly, MI practice during arm-immobilization was found to attenuate strength loss [12], prevent the impairment of movement preparation time [13], and counteract the slowdown in the sensorimotor representation of the immobilized limb [14]. Crew et al [15] and Bassolino et al [16] however failed to show that MI was effective in compensating the maladaptive plasticity induced by limb disuse.…”

Selective impairment of sensorimotor representations following short-term upper-limb immobilization

“…Neuronal evidence has indicated that limb non-use induces a decrease in motor cortex excitability contralateral to the immobilised limb (Avanzino, Bassolino, Pozzo, & Bove, 2011;Avanzino, Pelosin, Abbruzzese, Bassolino, Pozzo, & Bove, 2013;Facchini, Romani, Tinazzi, & Aglioti, 2002;Huber, Ghilardi, Massimini, Ferrarelli, Riedner, Peterson, & Tononi, 2006). In parallel, behavioral studies have shown that sensorimotor restriction alters the central functioning of the sensorimotor system and may disrupt motor performance (Bassolino, Bove, Jacono, Fadiga, & Pozzo, 2012;Huber et al, 2006;Moisello, Bove, Huber, Abbruzzese, Battaglia, Tononi, & Ghilardi, 2008) or action simulation (Meugnot, Almecija, & Toussaint, 2014;Meugnot, Agbangla, Almecija, & Toussaint, 2015;Toussaint & Meugnot, 2013) of the restricted and unrestricted limbs.…”

Massage can (re-)activate the lower limb sensorimotor representation of older adult inpatients.

“…Recently, to examine the central and functional effects of non-use of a limb, some researchers based their reasoning on the simulation theory (Jeannerod, 2001), which states that physical and simulated actions share the same sensorimotor representations and rely on similar mechanisms. The authors specifically examined whether internal sensorimotor representations are affected by the input/output restriction of signal processing following a short delay of upper-limb non-use (24 or 48 hours; Meugnot, Agbangla, Almecija, Toussaint, 2015;Meugnot, Almecija, Toussaint, 2014) by asking participants to solve mental rotation tasks using body or non-body stimuli that depended respectively on motor and visual imagery strategies, respectively. Based on a motor imagery strategy, the mental rotation tasks used body images (i.e., hand or foot) to assess the efficiency of specific internal sensorimotor representation (i.e., the upper-limb or the lower-limb representation, respectively).…”