title: The Early Indicators of Functional Decrease in Mild Cognitive Impairment.
abstract: OBJECTIVE
  Motor deficiency is associated with cognitive frailty in patients with Mild Cognitive Impairments (MCI). In this study we aimed to test the integrity in muscle synergies involved in an arm-pointing movement in functionally unimpaired MCI patients. We hypothesized that early motor indicators exist in this population at a preclinical level.
  
  
  METHODS
  Electromyographic signals were collected for 11 muscles in 3 groups: Young Adults (YA), Older Adults (OA), and MCI patients. The OA and MCI groups presented the same functional status. Each subject performed 20 arm-pointing movements from a standing position.
  
  
  RESULTS
  The main differences were (1) an earlier activation of the left Obliquus internus in MCI compared with OA group, (2) an earlier activation for the MCI compared with both OA and YA. The temporal differences in muscle synergies between MCI and OA groups were linked with executive functions of MCI patients, assessed by the trail making test. Moreover, the results show a delayed activation of the right Biceps Femoris and the right Erector Spinae at l3 in MCI and OA compared with YA.
  
  
  CONCLUSIONS
  The motor program changes highlighted in our patient MCI group suggest that discrete modifications of the motor command seem to exist even in the absence of functional impairment. Instead of showing an indication of delayed muscle activation in the MCI patients, our results highlight some early activation of several trunk muscles.
authors: Unité 1093, Cognition, Action et Plasticité Sensorimotrice, Institut National de la Santé et de la Recherche MédicaleDijon, France; Université de Bourgogne Franche Comté, Unité de Formation et de Recherche (UFR) Sciences et Techniques des Activités Physiques et Sportives (STAPS)Dijon, France; Institut de Formation aux Métiers de la Santé (IFMS), Nord Franche-Comté, Hôpital Nord Franche-ComtéMontbéliard, France.
authors: Alexandre
authors: A
authors: Kubicki
authors: Unité 1093, Cognition, Action et Plasticité Sensorimotrice, Institut National de la Santé et de la Recherche MédicaleDijon, France; Université Paris Ouest Nanterre La Défense, Unité de Formation et de Recherche (UFR) Sciences et Techniques des Activités Physiques et Sportives (STAPS)Nanterre, France; Centre de Recherche sur le Sport et le Mouvement, CeRSM, Unité de Formation et de Recherche (UFR) Sciences et Techniques des Activités Physiques et Sportives (STAPS)Nanterre, France.
authors: Lilian
authors: L
authors: Fautrelle
authors: Unité 1093, Cognition, Action et Plasticité Sensorimotrice, Institut National de la Santé et de la Recherche MédicaleDijon, France; Université de Bourgogne Franche Comté, Unité de Formation et de Recherche (UFR) Sciences et Techniques des Activités Physiques et Sportives (STAPS)Dijon, France.
authors: Julien
authors: J
authors: Bourrelier
authors: Unité 1093, Cognition, Action et Plasticité Sensorimotrice, Institut National de la Santé et de la Recherche MédicaleDijon, France; Centre Mémoire Ressources et Recherche, Centres Hospitaliers Universitaires (CHU), Dijon-BourgogneDijon, France.
authors: Olivier
authors: O
authors: Rouaud
authors: Unité 1093, Cognition, Action et Plasticité Sensorimotrice, Institut National de la Santé et de la Recherche MédicaleDijon, France; Unité de Formation et de Recherche (UFR), Santé, Université de Bourgogne Franche ComtéDijon, France.
authors: France
authors: F
authors: Mourey
keywords: Anticipatory Postural Adjustments; Mild Cognitive Impairments; cognitive functions; motor control; muscle synergy