ObjectiveTo investigate the neural mechanisms of subjects with anisometropic amblyopia using event-related potential (ERP) technology.MethodsNineteen subjects diagnosed with anisometropic amblyopia were consecutively recruited from the outpatients of the West China Hospital of Sichuan University from June 2013 to February 2014, and twenty normal subjects were recruited as control subjects. All subjects were given different orientation Gabor stimuli with three spatial frequencies (1, 2, 8 cpd) and their ERP was recorded. The differences of P3b, including amplitude and latency, were compared between amblyopic eye and fellow or control eye.ResultsAmong the three groups of amblyopic eye and fellow or control eye, there was no statistically significant difference in accuracy or response time at three spatial frequencies (P>0.05), in latency or amplitude of P3b at low spatial frequencies (1, 2 cpd) ((P>0.05), or in amplitude of P3b at high spatial frequency (8 cpd) (P>0.05). P3b latency of amblyopic eye extended at high spatial frequency (8 cpd), compared to fellow or control eye. Amblyopic eye was most significantly weakened in Brodmann area 17 at the P3b wave of each spatial frequency (1, 2, 8 cpd), and there was most significantly weakened in high spatial frequency (8 cpd).ConclusionThe P3b latency of amblyopic eye extended at high spatial frequency suggests that the cognitive function of amblyopia is impaired, at an extent, in the late visual processing stage.
There are few researches on the modulation effect of transcranial direct current stimulation(tDCS) on complex spatial cognition. Especially, the influence of tDCS on the neural electrophysiological response in spatial cognition is not yet clear. This study selected the classic spatial cognition task paradigm (three-dimensional mental rotation task) as the research object. By comparing the changes in behavior and event-related potentials in different modes of tDCS before, during and after the application of tDCS, this study analyzed the behavioral and neurophysiological effects of tDCS on mental rotation. The comparison between active-tDCS and sham-tDCS showed no statistically significant difference in behavior between different stimulation modes. Still, the changes in the amplitudes of P2 and P3 during the stimulation were statistically significant. Compared with sham-tDCS, the amplitudes of P2 and P3 in active-tDCS mode showed a greater decrease during the stimulation. This study clarifies the influence of tDCS on the event-related potentials of the mental rotation task. It shows that tDCS may improve the brain information processing efficiency during the mental rotation task. Also, this study provides a reference for an in-depth understanding and exploration of the modulation effect of tDCS on complex spatial cognition.
Event-related potentials (ERPs) are potential activities extracted from electroencephalogram (EEG) that are associated with specific stimuli. They possess the advantages of objectivity, ease of operation, and real-time reflection of cognitive processing in the brain. ERPs have been extensively utilized in studying pathophysiological mechanisms related to Alzheimer’s Disease (AD), Parkinson’s Disease (PD), stroke, schizophrenia, and other conditions. Epilepsy is a common neurological disorder wherein ERPs can be employed to explore the neuroelectrophysiological causes underlying cognitive impairment, anxiety, and depression in patients with epilepsy while providing an objective assessment. This article reviews the application of ERPs in patients with epilepsy.