Department of Psychology, Faculty of Science, University of Alberta, Edmonton, Alberta, Canada.
Neuropsychology Lab, Department of Psychology, University of Oldenburg, Oldenburg, Germany.
Psychophysiology. 2019 Nov;56(11):e13435. doi: 10.1111/psyp.13435. Epub 2019 Jul 23.
Most experiments using EEG recordings take place in highly isolated and restricted environments, limiting their applicability to real-life scenarios. New technologies for mobile EEG are changing this by allowing EEG recording to take place outside of the laboratory. However, before results from experiments performed outside the laboratory can be fully understood, the effects of ecological stimuli on brain activity during cognitive tasks must be examined. In this experiment, participants performed an auditory oddball task while also listening to concurrent background noises of silence, white noise, and outdoor ecological sounds, as well as a condition in which the tones themselves were at a low volume. We found a significantly increased N1 and decreased P2 when participants performed the task with outdoor sounds and white noise in the background, with the largest differences in the outdoor sound condition. This modulation in the N1 and P2 replicates what we have previously found outside while people rode bicycles. No behavioral differences were found in response to the target tones. We interpret these modulations in early ERPs as indicative of sensory filtering of background sounds and that ecologically valid sounds require more filtering than simple synthetic sounds. Our results reveal that much of what we understand about the brain will need to be updated as cognitive neuroscience research begins to step outside of the lab.
大多数使用脑电图记录的实验都是在高度隔离和受限的环境中进行的，这限制了它们在现实场景中的应用。移动脑电图新技术正在改变这种情况，允许在实验室外进行脑电图记录。然而，在充分理解实验室外实验的结果之前，必须研究生态刺激对认知任务期间大脑活动的影响。在这个实验中，参与者在听同时存在的背景噪声（包括静音、白噪声和户外生态声音）以及音调本身音量较低的情况下执行听觉Oddball 任务。我们发现，当参与者在户外声音和白噪声的背景下执行任务时，N1 和 P2 显著增加，在户外声音条件下差异最大。这种 N1 和 P2 的调制与我们之前在人们骑自行车时在户外发现的情况相同。对目标音调没有发现行为差异。我们将早期 ERP 中的这些调制解释为对背景声音的感官过滤的指示，并且生态有效声音比简单的合成声音需要更多的过滤。我们的结果表明，随着认知神经科学研究开始走出实验室，我们需要更新对大脑的许多理解。
