空间推理的脑机制:一项ERP研究

The Neural Basis of Spatial Reasoning:An Event-related Potential Study

记录14名正常成人完成四种空间推理及一种记忆任务时的事件相关电位,对空间推理的脑电活动特征进行考察。研究结果显示,在200ms-900ms窗口,推理任务比记忆任务诱发更大的正成分。在不同推理任务中,具体与抽象材料的单模型推理诱发相似的波形;有效的双模型任务比单模型任务诱发更大的P300-600。在200-600ms时间窗口,存在有效结论与无有效结论的双模型问题也诱发明显不同的ERP波形。研究结果表明,推理与记忆可能涉及不同的加工要求;在解决推理问题时,从200ms开始,被试就对刺激材料进行初步的加工与判断,随后对双模型问题可能采用有注解的单模型加工策略。另外,视觉表象并未明显影响空间推理过程。

The purpose of the present study was to disentangle the neurocognitive subprocesses underlying different spatial reasoning problems with the event-related potentials technique.Fourteen healthy young Chinese students（6 males and 8 females,mean age 25.2±2.2 years） without history of neurological disorders participated in this study.There were four kinds of three-term spatial reasoning tasks and one kind of memory tasks（baseline,BS）.The term orders are AB-CB in all tasks.All stimuli were generated with the Eprime 1.0 software and displayed in black against a white background on a computer screen.EEG was recorded from the scalp through 32 non-polarizable Ag/AgCl sintered electrodes in pre-configured caps,with a 500 Hz sampling rate using the Neuroscan EEG system. The ERP waveforms were time-locked to the onset of premise 2.Mean amplitudes in each time window were analyzed with the three-way repeated-measures analyses of variance.The behavioral results indicated that memory tasks were easier than reasoning tasks except for the absent valid multi-model problems.But both multi-model reasoning tasks were easier than one-model reasoning task.ERP data showed that reasoning tasks elicited more positive amplitudes than baseline tasks from 200ms to 900ms.The content-based spatial reasoning elicited a waveform similar to that of no-content spatial reasoning.One-model problem elicited different waveforms with valid twomodel problems in the time window of 300-600ms.Valid two-model problems elicited different waveform with two model and no-valid problems in the time window of 200-600ms. In conclusion,the behavioral data show that the place of indeterminate premises and the difficulty of spatial problems affected the process of resolving uncertain spatial reasoning.ERP data suggest that spatial reasoning and memory might reflect different requirement of attention resources.When confronted with a two-model problem,people process the stimulus and make a primary decision after 200ms,then the construction of a single mental model with an annotation.Moreover,visual images do not affect significantly spatial reasoning.