5 Clinical Trials for Various Conditions
The purpose of this study is to investigate several approaches for improving spatial perception and speech intelligibility in multitalker listening situations for hearing-aid users. The hypotheses are that spatial perception and speech intelligibility will be improved by (1) increased high-frequency audibility, (2) speech envelope enhancement, and/or (3) appropriate sound image externalization.
The overarching hypothesis to be evaluated using this protocol is that age-related hearing loss (ARHL) leads to shifts in the functional spatial boundaries between segregated and integrated auditory streams, and that hearing aid intervention that relies on directional processing schemes is most effective for those that have the poorest spatial sensitivity. One key component of the research design is to measure both behavioral and neurophysiological indices of an individual's spatial segregation boundary. The second key component is to measure the cost or benefit associated with hearing aid intervention in older hearing-impaired listeners. The final component is to relate cost and benefit of hearing aid intervention to spatial sensitivity measures that might predict the efficacy of clinical intervention.
This study in, healthy human subjects using fMRI and MRS (magnetic resonance spectroscopy) characterizes, how attention and acetylcholine affect visual perception and the brain's representation of the visual environment. Levels of acetylcholine in the cerebral cortex will be enhanced by administration of donepezil, an inhibitor of acetylcholinesterase. Half the subjects will receive donepezil and other half will receive placebo.
The purpose of this research study with a randomized controlled design is to examine the effects of prism adaptation treatment on two visual-spatial recovery components. After a stroke, an "internal GPS", locating where objects or people lie in a particular area of space, may be impaired. Alternately, a stroke may impair precise visual-spatial hand and body aiming movements. The research team wishes to discover whether prism adaptation treatment (two weeks of daily 20-min sessions of goal-directed movement with prism goggles) affects visual-spatial where or aiming errors selectively after stroke. This research represents one of the first attempts to apply what we know about the brain from neuroscience research, to modern clinical rehabilitation practices.
The purpose of this study is to learn more about how the brain allows people to focus on important objects and filter out unimportant ones when looking at visual images. Our senses provide us with a vast amount of information at any given moment in time. For example, visual scenes contain many different objects that cannot be processed simultaneously because of the limited processing capacity of the brain's visual system. Evidence suggests that a a network of brain regions selects relevant information and filters out irrelevant information when people view cluttered visual scenes. This study will use transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) to determine how the different brain regions involved in attentional control and filtering interact. Participants in this study will undergo computer tests, an MRI scan, and TMS. During the MRI, participants will look at pictures and count objects appearing on a screen. During the TMS, participants will perform a computer test. Participants' ability to pay attention will be tested with and without TMS. Participants may be asked to return for additional tests in the future....