Search PubMed⌕ Search
Home/Archive/PubMed

PubMed · 2735582

Visual evoked potential processing under acceleration stress.

G J Maskarinec·E A Trachtenberg·B Onaral
View original source ↗Export metadata ↓

Abstract

A study of the use of visual evoked potentials to detect acceleration induced blackout is presented. Decisions concerning the presence or absence of the visual evoked potential within the measured EEG were made using detection and estimation-based approaches. The performance of each technique is evaluated in two ways: (a) via a performance index (PI) which is introduced in this work, and (b) by the accuracy of pure detection. Variations of the main processing techniques such as output averaging and decision thresholding were also investigated.

Explore related subjects

AccelerationAerospace MedicineElectroencephalographyEvoked Potentials, VisualFourier AnalysisHumansMathematical ComputingStress, PhysiologicalTask Performance and AnalysisJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

G J Maskarinec, E A Trachtenberg, B Onaral. 1989. Visual evoked potential processing under acceleration stress.. https://doi.org/10.1007/bf02368044

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

KEEP EXPLORING

Related citations

PubMed1999

Muscle sympathetic nerve response to vestibular stimulation by sinusoidal linear acceleration in humans.

To clarify the effects of natural otolith stimulation on muscle sympathetic nerve activity (MSNA) in humans, eight male volunteers were seated in a linear accelerator (sled) during the recording of MSNA from the tibial nerve with microneurography, and also the recording of electrocardiogram, blood pressure measured with a Finapres device and thoracic impedance during movement. Sinusoidal linear acceleration with peak values of +/-0.10, 0.15 and 0.20 Gx were applied to the sitting subjects in the anteroposterior direction. Both the total activity and the burst rate of MSNA decreased during the sinusoidal linear acceleration, whereas the average heart rate, thoracic impedance and mean arterial pressure did not change significantly. These results suggest that moderate sinusoidal linear acceleration in the anteroposterior direction may suppress MSNA in humans.

Acceleration↗
PubMed1999

Characteristics of the VOR in response to linear acceleration.

The primate linear VOR (LVOR) includes two forms. First, eye-movement responses to translation [e.g., horizontal responses to interaural (i.a.) motion] help maintain binocular fixation on targets, and therefore a stable bifoveal image. The translational LVOR is strongly modulated by fixation distance, and operates with high-pass dynamics (> 1 Hz). Second, other LVOR responses occur that cannot be compensatory for translation and instead seem compensatory for head tilt. This reflects an otolith response ambiguity--that is, an inability to distinguish head translation from head tilt relative to gravity. Thus, ocular torsion is appropriately compensatory for head roll-tilt, but also occurs during IA translation, since both stimuli entail IA acceleration. Unlike the IA-horizontal response, IA torsion behaves with low-pass dynamics (with respect to "tilt"), and is uninfluenced by fixation distance. Interestingly, roll-tilt, like IA translation, also produces both horizontal (a translational reflex) and torsional (a tilt reflex) responses, further emphasizing the ambiguity problem. Early data from subjects following unilateral labyrinthectomy, which demonstrates a general immediate decline in translational LVOR responses, are also presented, followed by only modest recovery over several months. Interestingly, the usual high-pass dynamics of these reflexes shift to an even higher cutoff. Both eyes respond roughly equally, suggesting that unilateral otolith input generates a binocularly symmetric LVOR.

Acceleration↗
PubMed1999

Human ocular counterrolling during roll-tilt and centrifugation.

To test a hypothesis about how otoliths resolve roll-tilts from translations, we measured human ocular torsion position [ocular counterrolling (OCR)] to maintained linear acceleration stimuli. All subjects (n = 8) were tested in two conditions where the same magnitude of shear along an interaural axis was generated in one of two ways: either by roll-tilt on a tilt-chair in a 1-g environment, or by centripetal linear acceleration during constant velocity rotation 1 m from the axis of rotation on a fixed-chair human centrifuge. The interaural shear to the otoliths was the same for these two conditions, but the dorsoventral shear was different and for all eight subjects the OCR on the centrifuge was significantly greater than the torsion on the tilt-chair, although the resultant angle was in fact smaller on the centrifuge than on the tilt-chair. The results confirm that dorsoventral shear is important for determining OCR. The otoliths may resolve potential stimulus ambiguities between tilts and translations by virtue of the different patterns of interaural and dorsoventral shear that these stimuli generate.

Acceleration↗