Fig. 2: Single-trial rasters for example neurons show diversity of response types and tuning.
From: Large-scale single-neuron speech sound encoding across the depth of human cortex
a, Four example sentences with word- and phoneme-level transcriptions time aligned to the audio waveform. Phoneme/feature colours correspond to example units in c–m, which were labelled by hand for visualization purposes. b, Acoustic spectrogram of speech stimuli. Rasters for each neuron and sentence. Rows correspond to the number of repeats for that neuron and sentence. Coloured lines are the smoothed (50 ms window) PSTHs across trials. c,d, Two examples of neurons responding primarily to nasal sounds (for example, /m/, /n/). Note that even similarly tuned neurons can have very different spiking properties (for example, primarily bursting (p4-2-u79) versus sparse firing (p3-u18)). e, Neuron responding primarily to approximant sounds (for example, /l/, /r/, /w/). f,g, Two examples of neurons that are selectively responsive to fricatives (for example, /s/, /z/, /f/). h, Neuron selectively responsive to high/front vowels (for example, /i/, /ɪ/). i, Neuron primarily responsive to low/back vowels (for example, /ɑ/, /ʌ/, /ɔ/). j, Neuron primarily responsive to plosives (for example, /b/, /d/, /g/, /p/, /t/, /k/). k–m, Neurons responsive to sentence onsets. Some units show increased firing at onset (k,l), whereas others show delayed firing (m). a.u., arbitrary unit.
