PubMed Health⌕ Search

PubMed · 4090720

[Individual-typologic features of EEG structure].

Abstract

EEG monopolarly recorded in points F3, F4, O1, O2 of 20 healthy subjects in six states (quiet wakefulness with open or closed eyes, spontaneous button pressings in arbitrary moments of time, listening to clicks, reaction to clicks by pressing the button at random or at equal intervals between stimuli), were processed by means of the computer program transforming the raw EEG tracings to a sequence of stationary segments. The accumulated segments were divided into classes of "similar" ones by a two-stage procedure of cluster analysis. In each lead six types of segments were identified forming populations of structural units of an individual human EEG. Four types were recorded all over the brain: their spectra were of a great resemblance in different brain areas. The EEG of each individual was characterized by a certain combination of segment types which practically did not change by their quality in different states of the subject.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

M V Bodunov. [Individual-typologic features of EEG structure].. https://pubmed.ncbi.nlm.nih.gov/4090720/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Hearing lips and seeing voices: how cortical areas supporting speech production mediate audiovisual speech perception.

Observing a speaker's mouth profoundly influences speech perception. For example, listeners perceive an "illusory" "ta" when the video of a face producing /ka/ is dubbed onto an audio /pa/. Here, we show how cortical areas supporting speech production mediate this illusory percept and audiovisual (AV) speech perception more generally. Specifically, cortical activity during AV speech perception occurs in many of the same areas that are active during speech production. We find that different perceptions of the same syllable and the perception of different syllables are associated with different distributions of activity in frontal motor areas involved in speech production. Activity patterns in these frontal motor areas resulting from the illusory "ta" percept are more similar to the activity patterns evoked by AV(/ta/) than they are to patterns evoked by AV(/pa/) or AV(/ka/). In contrast to the activity in frontal motor areas, stimulus-evoked activity for the illusory "ta" in auditory and somatosensory areas and visual areas initially resembles activity evoked by AV(/pa/) and AV(/ka/), respectively. Ultimately, though, activity in these regions comes to resemble activity evoked by AV(/ta/). Together, these results suggest that AV speech elicits in the listener a motor plan for the production of the phoneme that the speaker might have been attempting to produce, and that feedback in the form of efference copy from the motor system ultimately influences the phonetic interpretation.

Auditory Perception↗

Top-down processes during auditory phoneme categorization in dyslexia: a PET study.

While persistence of subtle phonological deficits in dyslexic adults is well documented, deficit of categorical perception of phonemes has received little attention so far. We studied learning of phoneme categorization during an activation H(2)O(15) PET experiment in 14 dyslexic adults and 16 normal readers with similar age, handedness and performance IQ. Dyslexic subjects exhibited typical, marked impairments in reading and phoneme awareness tasks. During the PET experiment, subjects performed a discrimination task involving sine wave analogues of speech first presented as pairs of electronic sounds and, after debriefing, as syllables /ba/ and /da/. Discrimination performance and brain activation were compared between the acoustic mode and the speech mode of the task which involved physically identical stimuli; signal changes in the speech mode relative to the acoustic mode revealed the neural counterparts of phonological top-down processes that are engaged after debriefing. Although dyslexic subjects showed good abilities to learn discriminating speech sounds, their performance remained lower than those of normal readers on the discrimination task over the whole experiment. Activation observed in the speech mode in normal readers showed a strongly left-lateralized pattern involving the superior temporal, inferior parietal and inferior lateral frontal cortex. Frontal and parietal subparts of these left-sided regions were significantly more activated in the control group than in the dyslexic group. Activations in the right frontal cortex were larger in the dyslexic group than in the control group for both speech and acoustic modes relative to rest. Dyslexic subjects showed an unexpected large deactivation in the medial occipital cortex for the acoustic mode that may reflect increased effortful attention to auditory stimuli.

Auditory Perception↗