Department of Behavioral Science, National University of Distance Education (UNED), Juan del Rosal, 10, 28040, Madrid, Spain.
Department of Personality Psychology, National University of Distance Education (UNED), Madrid, Spain.
Psychol Res. 2019 Sep;83(6):1124-1136. doi: 10.1007/s00426-017-0959-2. Epub 2017 Dec 8.
The presentation of two pure tones to each ear separately with a slight difference in their frequency results in the perception of a single tone that fluctuates in amplitude at a frequency that equals the difference of interaural frequencies. This perceptual phenomenon is known as binaural auditory beats, and it is thought to entrain electrocortical activity and enhance cognition functions such as attention and memory. The aim of this study was to determine the effect of binaural auditory beats on long-term memory. Participants (n = 32) were kept blind to the goal of the study and performed both the free recall and recognition tasks after being exposed to binaural auditory beats, either in the beta (20 Hz) or theta (5 Hz) frequency bands and white noise as a control condition. Exposure to beta-frequency binaural beats yielded a greater proportion of correctly recalled words and a higher sensitivity index d' in recognition tasks, while theta-frequency binaural-beat presentation lessened the number of correctly remembered words and the sensitivity index. On the other hand, we could not find differences in the conditional probability for recall given recognition between beta and theta frequencies and white noise, suggesting that the observed changes in recognition were due to the recollection component. These findings indicate that the presentation of binaural auditory beats can affect long-term memory both positively and negatively, depending on the frequency used.
当分别向两只耳朵呈现两个具有轻微频率差异的纯音时,会产生一种幅度随频率波动的单一音,其频率等于两耳间的频率差。这种感知现象被称为双耳听觉节拍,它被认为可以使脑电活动同步,并增强注意力和记忆力等认知功能。本研究旨在确定双耳听觉节拍对长期记忆的影响。参与者(n=32)对研究目的一无所知,在分别暴露于β(20 Hz)或θ(5 Hz)频段的双耳听觉节拍、白噪声(作为对照条件)后,进行自由回忆和识别任务。β 频段的双耳听觉节拍暴露使更多的单词被正确回忆,识别任务中的 d' 敏感性指数更高,而θ 频段的双耳听觉节拍呈现则减少了正确记住的单词数量和敏感性指数。另一方面,我们在β和θ频率以及白噪声之间的识别后回忆的条件概率上没有发现差异,这表明观察到的识别变化归因于再认成分。这些发现表明,双耳听觉节拍的呈现可以根据使用的频率对长期记忆产生积极和消极的影响。