The role of the Supplementary Motor Area in time processing. The neural bases of timing mechanisms (0.1-100s range) are the subject of much debate. We hypothesise that the Supplementary Motor Area (SMA), a major cortical structure involving important dopaminergic pathways, subtends duration encoding, in the way depicted by the 'accumulator model'. Using transcranial magnetic stimulation (TMS) over the SMA, we will test healthy subjects in motor and perceptual timing tasks, compared to Parkinson' ....The role of the Supplementary Motor Area in time processing. The neural bases of timing mechanisms (0.1-100s range) are the subject of much debate. We hypothesise that the Supplementary Motor Area (SMA), a major cortical structure involving important dopaminergic pathways, subtends duration encoding, in the way depicted by the 'accumulator model'. Using transcranial magnetic stimulation (TMS) over the SMA, we will test healthy subjects in motor and perceptual timing tasks, compared to Parkinson's disease patients whose timing performance is impaired due to dopaminergic dysfunction. We expect TMS inhibitory effects to induce predictable performance trends, providing support for the accumulator model and the key role of the SMA in timing.Read moreRead less
Intracortical inhibition evaluated by paired-pulse TMS during choice and simple reaction time tasks. The research will investigate the neurophysiological processes responsible for the selection and initiation of movement in response to an external stimulus. Slowness in the initiation and execution of movement is a common feature of 'neurological aging', neurodegenerative disease, and brain injury. Understanding the brain mechanisms involved in response selection and movement initiation will pro ....Intracortical inhibition evaluated by paired-pulse TMS during choice and simple reaction time tasks. The research will investigate the neurophysiological processes responsible for the selection and initiation of movement in response to an external stimulus. Slowness in the initiation and execution of movement is a common feature of 'neurological aging', neurodegenerative disease, and brain injury. Understanding the brain mechanisms involved in response selection and movement initiation will provide information for the development of specific intervention techniques to improve motor function in these groups.Read moreRead less
The role of turgor in hyphal extension of the Ascomycete Neurospora crassa. Cellular expansion is an absolute necessity during the growth and development of plants and fungi. This process relies heavily upon the accumulation of inorganic ions. Osmotically driven water influx then creates the hydrostatic pressure that underlies the increase in cell volume. Cellular expansion is normally asymmetric and localised in one small region, such as hyphal tip. How does the cell maintain the turgor that dr ....The role of turgor in hyphal extension of the Ascomycete Neurospora crassa. Cellular expansion is an absolute necessity during the growth and development of plants and fungi. This process relies heavily upon the accumulation of inorganic ions. Osmotically driven water influx then creates the hydrostatic pressure that underlies the increase in cell volume. Cellular expansion is normally asymmetric and localised in one small region, such as hyphal tip. How does the cell maintain the turgor that drives expansion? How is expansion controlled spatially? These questions will be addressed in this project by comprehensive study of ion transport processes in a model organism, Neurospora crassa, using osmotic sensitive and transport mutants.Read moreRead less