听觉错觉的皮层诱发电位：双耳节拍。
Cortical evoked potentials to an auditory illusion: binaural beats.
作者信息
Pratt Hillel, Starr Arnold, Michalewski Henry J, Dimitrijevic Andrew, Bleich Naomi, Mittelman Nomi
机构信息
Evoked Potentials Laboratory, Behavioral Biology, Technion - Israel Institute of Technology, Haifa, Israel.
出版信息
Clin Neurophysiol. 2009 Aug;120(8):1514-24. doi: 10.1016/j.clinph.2009.06.014. Epub 2009 Jul 18.
OBJECTIVE
To define brain activity corresponding to an auditory illusion of 3 and 6Hz binaural beats in 250Hz or 1000Hz base frequencies, and compare it to the sound onset response.
METHODS
Event-Related Potentials (ERPs) were recorded in response to unmodulated tones of 250 or 1000Hz to one ear and 3 or 6Hz higher to the other, creating an illusion of amplitude modulations (beats) of 3Hz and 6Hz, in base frequencies of 250Hz and 1000Hz. Tones were 2000ms in duration and presented with approximately 1s intervals. Latency, amplitude and source current density estimates of ERP components to tone onset and subsequent beats-evoked oscillations were determined and compared across beat frequencies with both base frequencies.
RESULTS
All stimuli evoked tone-onset P(50), N(100) and P(200) components followed by oscillations corresponding to the beat frequency, and a subsequent tone-offset complex. Beats-evoked oscillations were higher in amplitude with the low base frequency and to the low beat frequency. Sources of the beats-evoked oscillations across all stimulus conditions located mostly to left lateral and inferior temporal lobe areas in all stimulus conditions. Onset-evoked components were not different across stimulus conditions; P(50) had significantly different sources than the beats-evoked oscillations; and N(100) and P(200) sources located to the same temporal lobe regions as beats-evoked oscillations, but were bilateral and also included frontal and parietal contributions.
CONCLUSIONS
Neural activity with slightly different volley frequencies from left and right ear converges and interacts in the central auditory brainstem pathways to generate beats of neural activity to modulate activities in the left temporal lobe, giving rise to the illusion of binaural beats. Cortical potentials recorded to binaural beats are distinct from onset responses.
SIGNIFICANCE
Brain activity corresponding to an auditory illusion of low frequency beats can be recorded from the scalp.
目的
确定与250Hz或1000Hz基频下3Hz和6Hz双耳节拍听觉错觉相对应的脑活动，并将其与声音起始反应进行比较。
方法
记录事件相关电位（ERP），以响应一只耳朵接收到的250Hz或1000Hz未调制纯音，另一只耳朵接收到高3Hz或6Hz的纯音，在250Hz和1000Hz基频下产生3Hz和6Hz幅度调制（节拍）的错觉。纯音持续时间为2000ms，间隔约1s呈现。确定ERP成分对纯音起始和随后节拍诱发振荡的潜伏期、幅度和源电流密度估计值，并在两种基频的不同节拍频率之间进行比较。
结果
所有刺激均诱发了纯音起始的P（50）、N（100）和P（200）成分，随后是与节拍频率相对应的振荡，以及随后的纯音结束复合体。低基频和低保节拍频率下，节拍诱发的振荡幅度更高。在所有刺激条件下，节拍诱发振荡的源主要位于左侧颞叶和颞下叶区域。起始诱发成分在不同刺激条件下无差异；P（50）的源与节拍诱发振荡的源有显著差异；N（100）和P（200）的源与节拍诱发振荡位于相同的颞叶区域，但为双侧性，还包括额叶和顶叶的贡献。
结论
来自左耳和右耳的 volley 频率略有不同的神经活动在中枢听觉脑干通路中汇聚并相互作用，以产生神经活动节拍来调节左颞叶的活动，从而产生双耳节拍的错觉。记录到的双耳节拍的皮层电位与起始反应不同。
意义
可以从头皮记录到与低频节拍听觉错觉相对应的脑活动。
Zotero 插件