Electrocortical Sources Related to Whole-Body Surface Translations during a Single- and Dual-Task Paradigm.

Appropriate reactive motor responses are essential in maintaining upright balance. However, little is known regarding the potential location of cortical sources that are related to the onset of a perturbation during single- and dual-task paradigms. The purpose of this study was to estimate the location of cortical sources in response to a whole-body surface translation and whether diverted attention decreases the N1 event-related potential (ERP) amplitude related to a postural perturbation.

Phenotypes of hypofrontality in older female fragile X premutation carriers.

Objective: To investigate the nature of cognitive impairments and underlying brain mechanisms in older female fragile X premutation carriers with and without fragile X-associated tremor/ataxia syndrome (FXTAS).

Methods: Extensive neuropsychological testing and cognitive event-related brain potentials (ERPs; particularly, the auditory P300) were examined in 84 female participants: 33 fragile X premutation carriers with FXTAS (mean age = 62.8 years), 25 premutation carriers without FXTAS (mean age = 55.