LTP-like plasticity in the visual system and in the motor system appear related in young and healthy subjects
نویسندگان
چکیده
LTP-like plasticity measured by visual evoked potentials (VEP) can be induced in the intact human brain by presenting checkerboard reversals. Also associated with LTP-like plasticity, around two third of participants respond to transcranial magnetic stimulation (TMS) with a paired-associate stimulation (PAS) protocol with a potentiation of their motor evoked potentials. LTP-like processes are also required for verbal and motor learning tasks. We compared effect sizes, responder rates and intercorrelations as well as the potential influence of attention between these four assessments in a group of 37 young and healthy volunteers. We observed a potentiation effect of the N75 and P100 VEP component which positively correlated with plasticity induced by PAS. Subjects with a better subjective alertness were more likely to show PAS and VEP potentiation. No correlation was found between the other assessments. Effect sizes and responder rates of VEP potentiation were higher compared to PAS. Our results indicate a high variability of LTP-like effects and no evidence for a system-specific nature. As a consequence, studies wishing to assess individual levels of LTP-like plasticity should employ a combination of multiple assessments.
منابع مشابه
Effects of visual deprivation on synaptic plasticity of visual cortex
TBS (Theta Burst Stimulation) and PBs (Primed Bursts) are among effective tetanic stimulations for induction of LTP in hippocampus. Recent studies have indicated that TBS is effective in LTP induction in layer III synapses of neocortex, only if applied to layer IV. However, the possibility of neocortical LTP induction using PBs, has not yet been investigated. Sensory deprivation greatly influ...
متن کاملEvaluation of Hemodynamic Response Function in Vision and Motor Brain Regions for the Young and Elderly Adults
Introduction: Prior studies comparing Hemodynamic Response Function (HRF) in the young and elderly adults based on fMRI data have reported inconsistent findings for brain vision and motor regions in healthy aging. It is shown that the averaging method employed in all previous works has caused this inconsistency. The averaging is so sensitive to outliers and noise. However, fMRI data are o...
متن کاملDevelopmental Effects of Melatonin on Synaptic Plasticity of Hippocampal CA1 Neurons in Visual Deprived Rats
Background & Aims: Change in visual experience impairs circadian rhythms. In this study, The effects of visual deprivation during critical period of brain development and melatonin intake on synaptic plasticity of hippocampal CA1 neurons were evaluated. Methods: This experimental study was done on male rats kept in standard 12 hour light/dark condition (L...
متن کاملP19: Long-Term Potentiation
The term synaptic plasticity points to a series of persistent changes related to the activity of synapses. Long-term potentiation (LTP) is a reflection of synaptic plasticity that has an important role in learning and memory. LTP is a long-lasting increase of synaptic activity due to enhancement of excitatory synaptic transmission after a high-frequency train of electrical stimulations. Differe...
متن کاملInvolvement of voltage-dependent calcium channels in synaptic plasticity of the rat visual cortex
In this study, involvement ofvoltage-dependent calcium channels in LTP of responses of rat visual cortex slices was analyzed. Field potentials including EPSP1 and EPSP2 from layers II/III were recorded through stimulation of layer IV. Whereas nifedipine, a L-type calcium channel blocker (L-VDCC), did not considerably affect the LTP of responses, but Ni2+, a relatively selective blocker of T-typ...
متن کامل