Date of Award

12-1992

Document Type

Thesis

Degree Name

Master of Science

Department

Department of Electrical and Computer Engineering

First Advisor

Steven K. Rogers, PhD

Abstract

A toposcope was constructed as a new tool to study signal frequency and phase relationships in electroencephalogram (EEG) records collected while subjects were experiencing motion sickness. This new tool, named TOPOS, is a software-based, multi-featured version of Grey Walter and Harold Shipton's device which they first produced in the late 1940s. The TOPOS graphical display permits the study of instantaneous frequency relationships between the input channels and a reference signal of fixed or varying frequency. TOPOS adds a correlation grid to aid observers in detecting channel-to-reference correlation levels. Users can also vary several display parameters via menus to optimize the analysis environment. Sinusoidal test inputs of known frequency produced recognizable and predictable patterns on the TOPOS display, depending on the existing channel-to-reference frequency relationships. Motion-sickness-affected EEG was input to TOPOS in order to study the correlation between the displays of each channel and four separate references: a 1.5-Hz sinusoid, and three channels of the EEG itself. Rapidly varying correlations were observed in each case.

AFIT Designator

AFIT-GSO-ENG-92D-03

DTIC Accession Number

ADA259024

Comments

The author's Vita page is omitted.

Download

Share

COinS