Kerick Scott E, Hatfield Brad D, Allender Laurel E
US Army Research Laboratory, Aberdeen Proving Ground, MD 21005, USA.
Aviat Space Environ Med. 2007 May;78(5 Suppl):B153-64.
Cortical dynamics of soldiers were examined during a reactive shooting task under varied task demands to investigate the effects of cognitive load on functional states of soldiers in real-time.
Task demand factors consisted of task load (single, dual), decision load (no-decision, choice-decision), and target-exposure time (short, long). The Dismounted Infantryman Survivability and Lethality Testbed (DISALT) shooting simulator was programmed to generate the eight shooting scenarios and record weapon aim-point data while EEG was acquired continuously during each scenario. Event-related spectral perturbation (ERSP) was derived from single-trial data time-locked to the onsets of targets and peak amplitude and latency measures were analyzed in theta (4-7 Hz) and upper alpha (11-13 Hz) frequency bands.
The results are as follows: 1) a stimulus-evoked ERSP theta peak exhibited higher amplitude in the parietal region for choice- vs. no-decision scenarios and longer latency in the right central and temporal regions for dual- vs. single-task scenarios; and 2) ERSP alpha exhibited a progressive increase following the onset of targets with less of an increase in the left central region for dual- vs. single-task scenarios.
ERSP theta synchronization reflects stimulus encoding and exhibits increased peak power with more complex decision demands and longer latency with secondary task demands, whereas ERSP alpha synchronization reflects motor preparation and exhibits less of an increase with secondary task demands during reactive target shooting tasks. This research contributes the first study of cortical dynamics of soldiers performing a reactive shooting task and has implications for theories of attention and cognitive workload, human factors engineering, and soldier performance.
在不同任务需求下的反应式射击任务中，对士兵的皮层动力学进行了研究，以实时调查认知负荷对士兵功能状态的影响。
任务需求因素包括任务负荷（单一、双重）、决策负荷（无决策、选择决策）和目标暴露时间（短、长）。对下车步兵生存能力和杀伤力测试平台（DISALT）射击模拟器进行编程，以生成八种射击场景，并记录武器瞄准点数据，同时在每个场景中持续采集脑电图。事件相关频谱微扰（ERSP）从与目标起始时间锁定的单次试验数据中导出，并在θ（4 - 7赫兹）和上α（11 - 13赫兹）频段分析峰值幅度和潜伏期测量值。
结果如下：1）刺激诱发的ERSP θ峰值在选择决策与无决策场景中，顶叶区域的幅度更高；在双重任务与单一任务场景中，右侧中央和颞叶区域的潜伏期更长；2）ERSP α在目标出现后呈现逐渐增加的趋势，在双重任务与单一任务场景中，左侧中央区域的增加幅度较小。
ERSP θ同步反映刺激编码，在决策需求更复杂时峰值功率增加，在有次要任务需求时潜伏期延长；而ERSP α同步反映运动准备，在反应式目标射击任务中，次要任务需求对其增加幅度的影响较小。本研究首次对执行反应式射击任务的士兵的皮层动力学进行了研究，对注意力和认知工作量理论、人因工程学以及士兵表现具有启示意义。
