Corticospinal facilitation during first and third person imagery

Motor imagery can be defined as the covert rehearsal of movement. Previous research with transcranial magnetic stimulation (TMS) has demonstrated that motor imagery increases the corticospinal excitability of the primary motor cortex in the area corresponding to the representation of the muscle involved in the imagined movement. This research, however, has been limited to imagery of oneself in motion. We extend the TMS research by contrasting first person imagery and third person imagery of index finger abduction-adduction movements. Motor evoked potentials were recorded from first dorsal interosseous (FDI) and abductor digiti minimi (ADM) during single pulse TMS. Participants performed first and third person motor imagery, visual imagery, and static imagery. Visual imagery involved non biological motion while static imagery involved a first person perspective of the unmoving hand. Relative to static imagery, excitability during imagined movement increased in FDI but not ADM. The facilitation in first person imagery adds to previous findings. A greater facilitation of MEPs recorded from FDI was found in third person imagery where the action was clearly attributable to another person. We interpret this novel result in the context of observed action and imagined observation of self action, and attribute the result to activation of mirror systems for matching the imagined action with an inner visuo-motor template

Corticospinal facilitation during first and third person imagery.

Motor imagery can be defined as the covert rehearsal of movement. Previous research with transcranial magnetic stimulation (TMS) has demonstrated that motor imagery increases the corticospinal excitability of the primary motor cortex in the area corresponding to the representation of the muscle involved in the imagined movement. This research, however, has been limited to imagery of oneself in motion. We extend the TMS research by contrasting first person imagery and third person imagery of index finger abduction-adduction movements. Motor evoked potentials were recorded from first dorsal interosseous (FDI) and abductor digiti minimi (ADM) during single pulse TMS. Participants performed first and third person motor imagery, visual imagery, and static imagery. Visual imagery involved non biological motion while static imagery involved a first person perspective of the unmoving hand. Relative to static imagery, excitability during imagined movement increased in FDI but not ADM. The facilitation in first person imagery adds to previous findings. A greater facilitation of MEPs recorded from FDI was found in third person imagery where the action was clearly attributable to another person. We interpret this novel result in the context of observed action and imagined observation of self action, and attribute the result to activation of mirror systems for matching the imagined action with an inner visuo-motor template

Kinaesthetic imagery and tool-specific modulation of corticospinal representations in expert tennis players

Specific physical or mental practice may induce short- and long-term neuroplastic changes in the motor system, and cause tools to become part of one\u2019s own body representation. Athletes who use tools as part of their practice may be an excellent model for assessing the neural correlates of possible bodily representation changes that are specific to extensive practice. We used single-pulse transcranial magnetic stimulation (TMS) to measure corticospinal excitability in forearm and hand muscles of expert tennis players and novices while they mentally practiced a tennis forehand, table tennis forehand, and a golf drive. The muscles of expert tennis players showed increased corticospinal facilitation during motor imagery of tennis but not golf or table tennis. Novices, although athletes, were not modulated across sports. Subjective reports indicated that only in the tennis imagery condition did experts differ from novices in the ability to form proprioceptive images and to consider the tool as an extension of the hand. Neurophysiological and subjective data converge to suggest a key role of long-term experience in modulating sensorimotor body representations during mental simulation of sport

Efeito das terapias associadas de imagem motora e de movimento induzido por restrição na hemiparesia crônica: estudo de caso

Este estudo analisa os efeitos da associação das terapias de imagem motora e de movimento induzido por restrição na reeducação funcional do membro superior (MS) de um paciente com deficit sensorial e motor determinado por acidente vascular encefálico (AVE). A terapia de imagem motora (IM) consistiu em: 1o, estimulo visual do espelho, em 3 sessões semanais de 30 a 60 minutos por 4 semanas; e 2o, IM com prática mental, em 3 sessões semanais de 15 minutos por 3 semanas. Por último foi aplicada a terapia de indução ao movimento por restrição do membro superior não-afetado por 14 dias, em 10 dos quais foi feita atividade funcional do membro parético por 6 horas diárias. Além da avaliação clinica da sensibilidade e medida da força de preensão palmar, antes do tratamento e após cada modalidade de terapia foi medida a amplitude de movimentos de ombro, cotovelo e punho e aplicada a escala de avaliação motora (EAM). Os escores dos quatro momentos da coleta foram comparados estatisticamente. Após o tratamento os resultados mostraram diferença significativa (pThis study assessed the efficacy of the association of motor imagery and constraint-induced movement therapies in functional rehabilitation of the upper limb in a patient with somatosensory and motor deficits following stroke. Motor imagery (MI) therapy, i.e., mental simulation of body image, consisted in: 1st, mirror visual stimulus, at three 30-60-minute weekly sessions for four weeks; and 2nd, MI with mental practice, at three 15-minute sessions per week for three weeks. Lastly, constraint-induced movement therapy was applied for 14 days, in 10 of which the patient underwent 6 hours daily of paretic limb functional training. The patient was assessed at baseline and at the end of each therapy modality as to clinical examination of sensation; hand grip strength; shoulder, elbow and wrist range of motion; and the motor assessment scale (MAS) was applied. Scores obtained at the four assessment moments were statistically compared. Results showed significant differences (p<0.05) after treatment: increased range of motion at all upper limb joints, increased hand grip strength, decrease in time of task performance at MAS, and recovery of clinical sensation, especially tactile detection and pressure sense. The association of IM and constraint-induced therapies thus proved effective in functional rehabilitation of the upper limb of the poststroke patient with chronic hemiparesis