Side of motor symptom onset predicts sustained attention deficits and motor improvements after attention training in Parkinson's disease.

Objective: Parkinson's disease (PD) side of motor symptom onset has been associated with distinct cognitive deficits; individuals with left-side onset (LPD) show more visuospatial impairments, whereas those with right-side onset (RPD) show more verbal impairments. Non-spatial attention is a critical cognitive ability associated with motor functioning that is right hemisphere lateralized but has not been characterized with regard to PD side of onset. We compared individuals with LPD and RPD on non-spatial attention tasks and examined differential responses to a 4-week sustained attention training program.

Effects of levetiracetam on axon excitability and synaptic transmission at the crayfish neuromuscular junction.

Levetiracetam (LEV) is a widely prescribed antiepileptic drug, but its actions on neuronal function are not fully characterized. Since this drug is believed to enter neurons by binding to a vesicular protein during endocytosis, we used motor axons of the crayfish opener neuromuscular junction to examine potential impacts of LEV on axon excitability. Two electrode current clamp from the inhibitory axon of the opener showed that LEV reduced action potential (AP) amplitude (AP ) and suppressed synaptic transmission, although the latter occurred with a longer delay than the reduction in AP .