Mesencephalic Locomotor Region and Presynaptic Inhibition during Anticipatory Postural Adjustments in People with Parkinson's Disease.

Individuals with Parkinson's disease (PD) and freezing of gait (FOG) have a loss of presynaptic inhibition (PSI) during anticipatory postural adjustments (APAs) for step initiation. The mesencephalic locomotor region (MLR) has connections to the reticulospinal tract that mediates inhibitory interneurons responsible for modulating PSI and APAs. Here, we hypothesized that MLR activity during step initiation would explain the loss of PSI during APAs for step initiation in FOG (freezers).

The Adapted Resistance Training with Instability Randomized Controlled Trial for Gait Automaticity.

Background: Deficits in the cerebellar locomotor region (CLR) have been associated with loss of gait automaticity in individuals with freezing of gait in Parkinson's disease (freezers); however, exercise interventions that restore gait automaticity in freezers are lacking. We evaluated the effects of the adapted resistance training with instability ([ARTI] complex exercises) compared with traditional motor rehabilitation (without complex exercises) on gait automaticity and attentional set-shifting. We also verified associations between gait automaticity change and CLR activation change previously published.

Loss of presynaptic inhibition for step initiation in parkinsonian individuals with freezing of gait.

Key Points: Individuals with freezing of gait (FoG) due to Parkinson's disease (PD) have small and long anticipatory postural adjustments (APAs) associated with delayed step initiation. Individuals with FoG ('freezers') may require functional reorganization of spinal mechanisms to perform APAs due to supraspinal dysfunction. As presynaptic inhibition (PSI) is centrally modulated to allow execution of supraspinal motor commands, it may be deficient in freezers during APAs.

Short-term resistance training with instability reduces impairment in V wave and H reflex in individuals with Parkinson's disease.

This study had two objectives: ) to compare the effects of 3 wk of resistance training (RT) and resistance training with instability (RTI) on evoked reflex responses at rest and during maximal voluntary isometric contraction (MVIC) of individuals with Parkinson's disease (PD) and ) to determine the effectiveness of RT and RTI in moving values of evoked reflex responses of individuals with PD toward values of age-matched healthy control subjects (HCs) (-score analysis). Ten individuals in the RT group and 10 in the RTI group performed resistance exercises twice a week for 3 wk, but only the RTI group included unstable devices. The HC group ( = 10) were assessed at pretest only.