Journal: Nature Communications

Article Title: Eye activity tracks task-relevant structures during speech and auditory sequence perception

doi: 10.1038/s41467-018-07773-y

Figure Lengend Snippet: Tracking of spoken sentences in EEG and EOG. a The speech material consists of a sequence of four-word sentences (monosyllabic words), which can be decomposed into a two-syllable noun phrase followed by a two-syllable verb phrase. The syllables are presented at a constant rate of 4 Hz, and therefore the presentation rates of phrases and sentences are 2 and 1 Hz, respectively. English words are shown in the illustration but the actual speech materials are in Chinese. b The EEG spectrum (channel Cz) shows three peaks of similar magnitude at the sentential, phrasal, and syllable rates (1, 2, and 4 Hz, respectively). The vertical EOG shows a clear sentential-rate response and a very weak syllabic-rate response. The horizontal EOG also shows a sentential-rate response peak but this response shows large individual variability and does not reach statistical significance. The significance of the spectral peaks is evaluated using bootstrap (the P -value, mean, and SEM reported in Supplementary Table ). The shaded area covers 1 SEM across participants ( N = 15) on each side, evaluated by bootstrap (same for plots of spectrum/waveform in other figures). In the illustration, the reference electrode is placed on one side but in the analysis the signal is referenced based on the average mastoid recording from both sides. c The topography of the EEG response shows a fronto-central distribution. d Sentential-rate response power is not correlated across the three measures, i.e., EEG, vertical EOG, and horizontal EOG (correlation not significantly larger than 0, P = 0.65, 0.75, and 0.73, respectively, one-sided bootstrap, not corrected for multiple comparisons). The power at each frequency is normalized by dividing the power averaged over two neighboring frequency bins. Each black dot is the data from one individual. * P < 0.05; ** P < 0.01

Article Snippet: EEG and EOG were recorded using a Biosemi ActiveTwo system.

Techniques: Sequencing

Journal: Nature Communications

Article Title: Eye activity tracks task-relevant structures during speech and auditory sequence perception

doi: 10.1038/s41467-018-07773-y

Figure Lengend Snippet: EEG, EOG, and eyetracking responses to sentences or random syllables. a Response spectra in four experimental conditions (columns) and for six neural/ocular measures (rows). The control condition presents random syllables instead of sentences. The blink rate measured by eyetracking, but not the saccade rate or pupil size, shows a reliable spectral peak at 1 Hz across conditions. The EEG signal is from channel Cz. Significance of each spectral peak is evaluated using bootstrap. The shaded area covers 1 SEM across participants ( N = 32) on each side. b The 1-Hz blink response is correlated with the 1-Hz vertical EOG response. In contrast, the 1-Hz components of other measures are not significantly correlated. Each dot is one participant. For all significance tests in the figure, the P -value, mean, and SEM are reported in Supplementary Table

Article Snippet: EEG and EOG were recorded using a Biosemi ActiveTwo system.

Techniques: Control

Journal: Nature Communications

Article Title: Eye activity tracks task-relevant structures during speech and auditory sequence perception

doi: 10.1038/s41467-018-07773-y

Figure Lengend Snippet: Temporal attention modulates the phase of sentence-tracking EEG/EOG activity. a Stimulus and task. The stimulus is a sequence of four-syllable sentences (shown in orange). The listeners have to attend to the 1st syllable of every sentence in one condition and attend to the 3rd syllable instead in the other condition. Unattended syllables are shaded in the illustration. The target phoneme, e.g., /f/, appears once in every trial but it may appear as the 1st, 2nd, 3rd, or 4th syllable in a sentence with equal probability. The listeners respond by pressing a key only when the target phoneme appears in the syllables they attend to. In the illustration, T means that a target appears while Ø means that no target appears. The trial structure is described in more details in Supplementary Fig. . b Response waveform (0.5–4.5 Hz) and the waveforms filtered into 1-Hz wide bands centered at 1 and 2 Hz, respectively. The response near 1 Hz is strongly modulated by attention but the response near 2 Hz is not. The onset of the 1st syllable of each sentence is marked by a dashed vertical line while the 3rd syllable is marked by a solid line. The shaded areas in this panel and panel c cover 1 SEM across participants ( N = 15) on each side. The EEG signal is from channel Cz. c EEG and EOG response spectra. Spectral peaks at the sentential and phrasal rates are observed for EEG and EOG in both conditions. For each spectral peak, the P -value, mean, and SEM are shown in Supplementary Table . d The response phase extracted by the Fourier analysis. The shaded area covers the 95% confidence interval of the mean phase. If the phase difference between conditions is significant, stars are marked near the figure title. See text for the exact confidence interval. * P < 0.05; ** P < 0.01

Article Snippet: EEG and EOG were recorded using a Biosemi ActiveTwo system.

Techniques: Activity Assay, Sequencing

Journal: Nature Communications

Article Title: Eye activity tracks task-relevant structures during speech and auditory sequence perception

doi: 10.1038/s41467-018-07773-y

Figure Lengend Snippet: EOG and EEG tracking of sentences for temporally jittered syllables. a EEG and EOG responses to each of the four syllables in a sentence. The response is averaged over sentences and participants, and the shaded area covers 1 SEM. The dotted curve shows the response averaged over all four syllables. b The response to temporally jittered syllables is time warped to simulate the response to an isochronous syllable sequence. The spectrum of the simulated response shows a peak at the sentential rate for EEG, vertical EOG, and horizontal EOG. See Supplementary Table for the exact P -value, mean, and variance measures. * P < 0.05; ** P < 0.01

Article Snippet: EEG and EOG were recorded using a Biosemi ActiveTwo system.

Techniques: Sequencing

Journal: Nature Communications

Article Title: Eye activity tracks task-relevant structures during speech and auditory sequence perception

doi: 10.1038/s41467-018-07773-y

Figure Lengend Snippet: Waveform of the blink rate and vertical EOG within each high-level structure in Experiments 1–5. a Timecourses of the blink rate and vertical EOG within each high-level structure. For Experiments 3–5, the onset of the attended unit is denoted by a triangle on the top. Black color represents conditions when attention is directed to the beginning of the structure while red color represents conditions when attention is directed to the midpoint of the structure. Other conditions are labeled in the figure. In Experiment 4, when the eyes are closed, clear phase opposition between conditions is only observed near the end of each trial (Fig. ) and therefore only the last 3 s of responses in each trial are averaged in this analysis. In Experiment 5, the response is aligned based on the 5th shape, which therefore is at time 0. b The time lag at which the blink/EOG signal reaches its maximal. Since the sequence structure is periodic, the estimated time lag could be advanced or delayed by an integer number of sequence periods. The error bar shows the 95% confidence interval, evaluated using bootstrap. In the bootstrap procedure, time lags from resampled data are converted into phase angles and averaged using the circular mean. c The cross-correlation function between single-trial blink signal and vertical EOG. A positive correlation is observed at time lag 0 in Experiments 2 and 4, in which EOG and eyetracking are simultaneously recorded

Article Snippet: EEG and EOG were recorded using a Biosemi ActiveTwo system.

Techniques: Labeling, Sequencing

Journal: Nature Communications

Article Title: Eye activity tracks task-relevant structures during speech and auditory sequence perception

doi: 10.1038/s41467-018-07773-y

Figure Lengend Snippet: Timecourse of the EOG power before, during, and after the stimulus. The vertical orange lines denote the onset and offset of the stimulus sequence. The upper and lower panels show vertical and horizontal EOG, respectively. The curves show the average of the single-trial EOG power, i.e., square of the EOG waveform. The solid and dashed curves show the eyes-closed and eyes-open conditions, respectively. Shaded area is 1 SEM across participants on each side. The EOG power is lower during the stimulus, compared with the pre-stimulus and post-stimulus periods (bootstrap, significance shown by stars in the same color as the lines, * P < 0.05, ** P < 0.01). See Supplementary Table for the exact P -value, mean, and variance measures

Article Snippet: EEG and EOG were recorded using a Biosemi ActiveTwo system.

Techniques: Sequencing