Title

Cortical electrical responses occurring prior to speech initiation

Presentation Type

Poster

Abstract

The readiness potential is an event-related potential which refers to the electrical stimulus in the brain that occurs before voluntary muscle movement. Electrical brain potentials have proven to be extremely useful for diagnosis, treatment and research in the auditory system, and are expected to be of equal importance for the speech system. The purpose of this research was to establish a real-time event related brain electrical potential system. In previous studies the marking point for determining the pre- event time epoch has been an Electromyographic (EMG) source. The data are typically acquired off-line and later averaged. This research uses a vocal signal as the marking point, and displays in real time the event-related potential. Subjects were University of Montana students. Electrodes were recorded with silver-silver chloride active electrodes positioned at the vertex, Cz, using the 10-20 system. The left earlobe were used as the reference. The ground was established at the opposite earlobe. Biological pre-amplifiers were used to amplify the weak bioelectric signals 100,000 times. Each time epoch was sampled at 25600 samples/sec. One second of these signals were averaged for 100 trials just prior to initiation of the words or syllables. The inter-trial interval was approximately 25 seconds. For the 100 trials, each trial was saved. Separate odd and even event potentials were averaged. Digital band-pass filters were used to observe the negative potential and also to observe the microstructure within the waveform. The obtained waveform was consistent and reliable between and within subjects. The microstructure of the waveform was also obtained showing specific waveform morphology. There are a number of clinical outcomes that can be beneficial from finding a repeatable signal, including diagnosis and treatment of: apraxia, speech disorders resulting from traumatic brain injury, stuttering, nonverbal behavior in children, and individuals who have experienced a stroke.

Category

Life Sciences

This document is currently not available here.

Share

COinS
 
Apr 15th, 3:00 PM Apr 15th, 4:00 PM

Cortical electrical responses occurring prior to speech initiation

The readiness potential is an event-related potential which refers to the electrical stimulus in the brain that occurs before voluntary muscle movement. Electrical brain potentials have proven to be extremely useful for diagnosis, treatment and research in the auditory system, and are expected to be of equal importance for the speech system. The purpose of this research was to establish a real-time event related brain electrical potential system. In previous studies the marking point for determining the pre- event time epoch has been an Electromyographic (EMG) source. The data are typically acquired off-line and later averaged. This research uses a vocal signal as the marking point, and displays in real time the event-related potential. Subjects were University of Montana students. Electrodes were recorded with silver-silver chloride active electrodes positioned at the vertex, Cz, using the 10-20 system. The left earlobe were used as the reference. The ground was established at the opposite earlobe. Biological pre-amplifiers were used to amplify the weak bioelectric signals 100,000 times. Each time epoch was sampled at 25600 samples/sec. One second of these signals were averaged for 100 trials just prior to initiation of the words or syllables. The inter-trial interval was approximately 25 seconds. For the 100 trials, each trial was saved. Separate odd and even event potentials were averaged. Digital band-pass filters were used to observe the negative potential and also to observe the microstructure within the waveform. The obtained waveform was consistent and reliable between and within subjects. The microstructure of the waveform was also obtained showing specific waveform morphology. There are a number of clinical outcomes that can be beneficial from finding a repeatable signal, including diagnosis and treatment of: apraxia, speech disorders resulting from traumatic brain injury, stuttering, nonverbal behavior in children, and individuals who have experienced a stroke.