Jourahmad Zahra, Mathura Raissa K, Mattar Layth S, Franch Melissa C, Paulo Danika L, Hasen Mohammed, Provenza Nicole R, Hayden Benjamin Y, Sheth Sameer A, Bartoli Eleonora, Watrous Andrew J
Baylor College of Medicine, Department of Neurosurgery, Houston, TX.
Department of Electrical and Computer Engineering, Rice University, Houston, TX.
bioRxiv. 2025 Sep 3:2025.09.03.674012. doi: 10.1101/2025.09.03.674012.
Neural oscillations play a critical role in shaping neuronal firing patterns. While phase-locked neuronal firing ("phase tuning") has been extensively studied in animal models and human invasive recordings, much less is known about whether neurons show preferential firing at specific oscillatory frequencies, termed frequency tuning. Here, we employ human intracranial recordings across several brain regions including hippocampus, entorhinal cortex, anterior and posterior cingulate cortex, and orbitofrontal cortex to test the hypothesis that neurons exhibit frequency-specific firing. We analyzed 357 single units recorded simultaneously with local field potentials in 19 neurosurgical patients during awake resting. We estimated the instantaneous frequency of the LFP using adaptive spectral decomposition and assessed frequency tuning of each neuron while controlling for changes in firing rate unrelated to frequency changes. We found 27% neurons exhibited increased or decreased firing within specific frequencies, most commonly within the low-theta range (<10 Hz). Neurons exhibiting frequency tuning were distinct from those displaying phase tuning, and both types of tuning were observed across multiple brain regions with no anatomical preference. Together, our results demonstrate that the instantaneous frequency of neural oscillations modulates neuronal firing which may serve as an additional mechanism for information processing in the human brain, opening new avenues for frequency-targeted neural stimulation.
神经振荡在塑造神经元放电模式中起着关键作用。虽然锁相神经元放电（“相位调谐”）在动物模型和人类侵入性记录中已得到广泛研究，但对于神经元是否在特定振荡频率下表现出优先放电（即频率调谐），我们了解得还很少。在这里，我们利用人类颅内记录，覆盖包括海马体、内嗅皮质、前扣带回和后扣带回皮质以及眶额皮质在内的多个脑区，来检验神经元表现出频率特异性放电这一假设。我们分析了19名神经外科患者在清醒休息期间与局部场电位同时记录的357个单个神经元。我们使用自适应谱分解估计局部场电位的瞬时频率，并在控制与频率变化无关的放电率变化的同时，评估每个神经元的频率调谐。我们发现27%的神经元在特定频率范围内放电增加或减少，最常见于低θ范围（<10Hz）。表现出频率调谐的神经元与表现出相位调谐的神经元不同，并且在多个脑区都观察到了这两种调谐类型，没有解剖学上的偏好。总之，我们的结果表明，神经振荡的瞬时频率调节神经元放电，这可能是人类大脑信息处理的一种额外机制，为频率靶向神经刺激开辟了新途径。
