Twelve healthy subjects received whole-body perturbations while seated in a tilting chair that required a compensatory upper limb reaction to regain balance following instability. The influence of perturbation amplitude (stimulus-dependent challenge- slow vs. fast perturbations) and task condition (context-dependent challenge- unrestricted vs. restricted movement) on EDR timing and magnitude parameters were examined. While EDR latency was consistent across conditions with onset occuring approximately 2 s after the

GW786034 concentration perturbation, peak-to-peak EDR amplitude was influenced by both stimulus-dependent and context-dependent challenges and also mirrored postural response amplitude. Compared to the Slow condition, EDR amplitude was 27 +/- 6% larger in the Fast condition (p = 0.0004). Similarly, ARN-509 concentration EDR amplitude was 244 +/- 86% larger in the Restricted task condition relative to the Unrestricted task condition (p=0.006). Context-dependent EDR modulation suggests that autonomic reactivity is associated with some higher level of processing independent of the degree of challenge related to stimulus characteristics. This work has potential implications for understanding determinants of central nervous system reactivity

among individuals with impaired limb control where the recovery challenge is uniquely linked to the context. (C) 2010 Elsevier Ireland Ltd. All rights reserved.”
“Dementia with Lewy Bodies (DLB) is a common neurodegenerative disorder of the aging population characterized by alpha-synuclein accumulation in cortical and subcortical regions. Although neuropathology in advanced age has been investigated in dementias such as Alzheimer Disease (AD), severity of the neuropathology in the oldest old with DLB remains uncharacterized. For this purpose we compared characteristics of DLB cases divided into three age groups 70-79, 80-89 and >= 90 years (oldest old). Neuropathological indicators and levels of synaptophysin were assessed and correlated with clinical measurements of cognition and dementia severity. These

studies showed that frequency Arachidonate 15-lipoxygenase and severity of DLB was lower in 80-89 and >= 90 year cases compared to 70-79 year old group but cognitive impairment did not vary with age. The extent of AD neuropathology correlated with dementia severity only in the 70-79 year group, while synaptophysin immunoreactivity more strongly associated with dementia severity in the older age group in both DLB and AD. Taken together these results suggest that the oldest old with DLB might represent a distinct group. (C) 2010 Elsevier Ireland Ltd. All rights reserved.”
“This study analyzed the balance strategies of ballet dancers during postural equilibrium in three single leg balance conditions with and without vision and regard to age.