Prada Laura, Barceló Francisco, Herrmann Christoph S, Escera Carles
Laboratory of Neuropsychology, University of Illes Balears, Mallorca, Spain; Asociación de Neuropsicología Balear (ANEBA), Mallorca, Spain.
Psychophysiology. 2014 Jul;51(7):658-72. doi: 10.1111/psyp.12210. Epub 2014 Mar 27.
Delta oscillations contribute to the human P300 event-related potential evoked by oddball targets, although it is unclear whether they index contextual novelty (event oddballness, novelty P3, nP3), or target-related processes (event targetness, target P3b). To examine this question, the electroencephalogram (EEG) was recorded during a cued task-switching version of the Wisconsin card-sorting test. Each target card was announced by a tone cueing either to switch or repeat the task. Novel sound distracters were interspersed among trials. Time-frequency EEG analyses revealed bursts of delta (2-4 Hz) power associated with enhanced nP3 amplitudes to both task-switch cues and novel distracters-but no association with target P3b. These findings indicate that the P300-delta response indexes contextual novelty regardless of whether novelty emanates from endogenous (new task rules) or exogenous (novel distracters) sources of information.
δ振荡对由异常刺激目标诱发的人类P300事件相关电位有影响，尽管尚不清楚它们是指示情境新颖性（事件异常性、新颖性P3、nP3），还是与目标相关的过程（事件目标性、目标P3b）。为了研究这个问题，在威斯康星卡片分类测试的线索任务切换版本中记录了脑电图（EEG）。每个目标卡片通过提示切换或重复任务的音调来宣布。在试验中穿插了新颖的声音干扰物。时频脑电图分析显示，与任务切换线索和新颖干扰物的nP3振幅增强相关的δ（2-4Hz）功率爆发——但与目标P3b无关。这些发现表明，无论新颖性是源于内源性（新任务规则）还是外源性（新颖干扰物）信息源，P300-δ反应都指示情境新颖性。
