An EEG-ECG Dataset of Stress and Mental Workload during Cognitive Tasks

A modified version of the Montreal Imaging Stress Task (MIST) was employed to investigate stress-induced neural and physiological changes. The task was adapted to suit the experimental protocol and consisted of computer-based arithmetic problems presented under two conditions: a neutral baseline and a stress-inducing condition. A within-subject design was used, with each participant completing both conditions in separate sessions spaced two weeks apart to minimize carryover effects. Each session consisted of seven stages: task familiarization, an eyes-open resting baseline, four arithmetic task levels (AC1–AC4) of increasing difficulty, and a post-task recovery period. In the neutral condition, the task was designed to assess cognitive workload without inducing stress. After a non-recorded training phase, EEG and ECG signals were recorded during a 5-minute eyes-open baseline while participants fixated on a dot. Participants then completed four arithmetic levels: single-digit addition and subtraction (AC1), small-scale multiplication (AC2), multi-operand expressions (AC3), and expressions including division (AC4). Immediate correctness feedback was provided after each response, with no time constraints or performance pressure. A 5-minute recovery period followed the final task. The stress condition followed the same structure but incorporated psychosocial stressors, including response time limits, visible countdown indicators, accuracy manipulation to maintain performance below 50%, and evaluative feedback such as “time out” messages. Performance scores were displayed after each task block to increase performance pressure and induce stress. ECG signals were recorded using bipolar limb leads (Lead I and Lead II) and amplified using an ECG acquisition system. Data were sampled at 1,000 Hz and bandpass filtered between 0.3 and 200 Hz. EEG data were recorded from eight scalp electrodes (Fp1, Fp2, F3, F4, P3, P4, T3, and T4) following the international 10–20 system, referenced to bilateral mastoids. Signals were acquired using an EEG amplifier at a sampling rate of 2,000 Hz, with electrode impedances maintained below 10 kΩ. ECG signals were further high-pass filtered at 1 Hz and inspected for cardiac abnormalities. EEG preprocessing was conducted using dedicated analysis software, applying a 1 Hz high-pass filter and a 50 Hz notch filter. Artifact rejection excluded segments exceeding ±150 µV, eye-blink artifacts were manually removed based on frontal channels, and clean 2-second EEG segments were extracted for subsequent analysis.本研究采用改良版蒙特利尔影像应激任务（Montreal Imaging Stress Task, MIST），以探究应激诱导的神经与生理变化。该任务适配实验方案进行调整，包含两种实验条件下的计算机化算术任务：中性基线条件与应激诱导条件。实验采用被试内设计，所有参与者均在间隔两周的独立会话中完成两种条件，以最小化遗留效应。每个会话包含七个阶段：任务熟悉化、睁眼静息基线、难度递增的四级算术任务（AC1–AC4）以及任务后恢复期。 在中性条件下，任务旨在评估认知负荷而不引发应激。在未记录的训练阶段后，参与者注视光点完成5分钟睁眼基线期，期间记录脑电图（Electroencephalogram, EEG）与心电图（Electrocardiogram, ECG）信号。随后参与者完成四级算术任务：一位数加减运算（AC1）、小规模乘法运算（AC2）、多运算符表达式运算（AC3）以及包含除法的表达式运算（AC4）。每次作答后会提供即时正确性反馈，且无时间限制与表现压力。最终任务结束后设有5分钟恢复期。 应激条件结构与中性条件一致，但融入了心理社会应激源：包括作答时限、可见倒计时指示器、将准确率调控至50%以下的准确性操控，以及“超时”这类评价性反馈。每个任务模块结束后会展示表现得分，以增强表现压力并诱发应激。 研究采用双极肢体导联（导联I与导联II）记录心电图信号，并通过心电图采集系统进行放大。数据以1000 Hz采样，并在0.3至200 Hz频段内进行带通滤波。脑电图数据依据国际10–20系统，采用双侧乳突作为参考电极，采集8个头皮电极（Fp1、Fp2、F3、F4、P3、P4、T3与T4）的信号。通过脑电图放大器以2000 Hz的采样率采集信号，且保持电极阻抗低于10 kΩ。 后续对心电图信号施加1 Hz高通滤波，并检查心脏异常情况。脑电图预处理采用专用分析软件完成，依次施加1 Hz高通滤波与50 Hz陷波滤波。通过剔除幅值超出±150 µV的片段实现伪迹排除，基于额叶通道手动剔除眼动伪迹，并提取时长为2秒的纯净脑电图片段用于后续分析。