Background: Prismatic Adaptation (PA) is a visuomotor procedure inducing a shift of the visual ﬁeld that has been shown to modulate activation of a number of brain areas, in posterior (i.e. parietal cortex) and anterior regions (i.e. frontal cortex). This neuromodulation could be useful to study neural mechanisms associated with either postural measures such as the distribution of plantar pressure or to the generation of muscle strength. Indeed, plantar pressure distribution is associated to activation of high-level cognitive mechanisms taking place within the posterior regions of the brain dorsal stream, especially of the right hemisphere. Conversely, hand force mostly rely on sensorimotor mechanisms, fulﬁlled by anterior regions of the brain and involving both hemispheres. Research question: Since PA eﬀects have been reported to aﬀect both sensorimotor and higher level cognitive processes, is it possible to hypothesize a modulation of both hands strenght and plantar pressure after PA? Methods: Forty-six healthy subjects (male=23; mean age=25 ± 3 years) were randomly divided into two groups: a leftward prismatic adaptation group (l-PA) and a rightward prismatic adaptation group (r-PA). Hand strength and plantar pressure were assessed, immediately before and after PA, using the handgrip task and baropodometric measurement, respectively. Results: Both l-PA and r-PA induced a signiﬁcant decrease of strength in the hand contralateral to the lenses deviation side. Only r-PA was associated with an increase of the forefoot plantar pressure in both feet. Modulation of interhemispheric inhibitory processes at sensorimotor and higher cognitive level may account for the present results. Signiﬁcance: PA exerts eﬀects on body posture and hand strength relying on diﬀerent mechanisms. The PA eﬀects on hand strength are probably related to the modulation of interhemispheric inhibition of sensorimotor processes, involving both hemispheres. The PA eﬀects on body posture are probably related to modulation of body representation, involving mainly the right hemisphere.
|Numero di pagine||6|
|Rivista||GAIT & POSTURE|
|Stato di pubblicazione||Published - 2020|