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Feasibility of Multi-Component Spatio-Temporal Modeling of Cognitively Generated EEG Data and its Potential Application to Research in Functional Anatomy and Clinical NeuropathologyZeman, Philip Michael 29 October 2013 (has links)
This dissertation is a compendium of multiple research papers that, together, address two
main objectives. The first objective and primary research question is to determine
whether or not, through a procedure of independent component analysis (ICA)-based data
mining, volume-domain validation, and source volume estimation, it is possible to
construct a meaningful, objective, and informative model of brain activity from scalpacquired
EEG data. Given that a methodology to construct such a model can be created,
the secondary objective and research question investigated is whether or not the sources
derived from the EEG data can be used to construct a model of complex brain function
associated with the spatial navigation and the virtual Morris Water Task (vMWT).
The assumptions of the signal and noise characteristics of scalp-acquired EEG data were
discussed in the context of what is currently known about functional brain activity to
identify appropriate characteristics by which to separate the activities comprising EEG
data into parts. A new EEG analysis methodology was developed using both synthetic
and real EEG data that encompasses novel algorithms for (1) data-mining of the EEG to
obtain the activities of individual areas of the brain, (2) anatomical modeling of brain
sources that provides information about the 3-dimensional volumes from which each of
the activities separated from the EEG originates, and (3) validation of data mining results
to determine if a source activity found via the data-mining step originates from a distinct
modular unit inside the head or if it is an artefact. The methodology incorporating the
algorithms developed was demonstrated for EEG data collected from study participants
while they navigated a computer-based virtual maze environment. The brain activities of
participants were meaningfully depicted via brain source volume estimation and
representation of the activity relationships of multiple areas of the brain. A case study
was used to demonstrate the analysis methodology as applied to the EEG of an individual
person. In a second study, a group EEG dataset was investigated and activity
relationships between areas of the brain for participants of the group study were
individually depicted to show how brain activities of individuals can be compared to the
group.
The results presented in this dissertation support the conclusion that it is feasible to use
ICA-based data mining to construct a physiological model of coordinated parts of the
brain related to the vMWT from scalp-recorded EEG data. The methodology was
successful in creating an objective and informative model of brain activity from EEG
data. Furthermore, the evidence presented indicates that this methodology can be used to
provide meaningful evaluation of the brain activities of individual persons and to make
comparisons of individual persons against a group.
In sum, the main contributions of this body of work are 5 fold. The technical
contributions are: (1) a new data mining algorithm tailored for EEG, (2) an EEG
component validation algorithm that identifies noise components via their poor
representation in a head model, (3) a volume estimation algorithm that estimates the
region in the brain from which each source waveform found via data mining originates,
(4) a new procedure to study brain activities associated with spatial navigation. The main
contribution of this work to the understanding of brain function is (5) evidence of specific
functional systems within the brain that are used while persons participate in the vMWT
paradigm (Livingstone and Skelton, 2007) examining spatial navigation. / Graduate / 0541 / 0622 / 0623
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The Effects of Eticlopride on Morris Water Task Performance in Male and Female Rats Neonatally Treated with QuinpiroleBrown, Russell W., Thompson, Kimberly N., Click, Ivy A., Best, Razaria A.C., Thacker, Stephanie K., Perna, Marla K. 01 July 2005 (has links)
RATIONALE: Previous studies have shown that neonatal quinpirole treatment which results in long-term dopamine D2 receptor supersensitization (D2 receptor priming) produces cognitive deficits in preweanling and adult rats behaviorally tested on the Morris water task (MWT).OBJECTIVE: This study was designed to analyze whether pretraining administration of the D2 antagonist eticlopride alleviates cognitive deficits produced by neonatal quinpirole treatment.METHODS: Both male and female Sprague-Dawley rats were treated with quinpirole HCl (1 mg/kg) or saline from postnatal days 1 to 21. From P22 to P24, rats were tested on the place version of the MWT in which a hidden platform remains stationary throughout training. From P25 to P28, rats were tested on the match-to-place version of the MWT, and rats are given a pair of daily training trials to locate the hidden platform that was moved to a new location each day. Fifteen minutes before each training session, rats were intraperitoneally administered with eticlopride (0.01 or 0.02 mg/kg) or saline.RESULTS: Pretraining eticlopride treatment alleviated cognitive deficits produced by neonatal quinpirole treatment in both male and female rats on the place version of the MWT, as well as in males tested on the match-to-place version of the MWT. However, there were no significant deficits produced by neonatal quinpirole treatment in females tested on the match-to-place version of the MWT, and control males demonstrated superiority over control females on this version of the task.CONCLUSIONS: Pretraining administration of the dopamine D2 antagonist eticlopride alleviated cognitive deficits produced by neonatal quinpirole treatment. However, it appears that the dopamine D2 receptor may have a more important influence on cognitive performance in males than in females, which may be related to increased sensitivity of the D2 receptor in males.
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Previous Spatial Memory Training and Nicotine Administration Alleviates Cognitive Deficits Produced by Medial Frontal Cortex Lesions in Rats.Norris, Rachel L 06 May 2006 (has links) (PDF)
Rats were administered nicotine (0.3 mg/kg) for 11 consecutive days before and after an electrolytic medial frontal cortex lesion. Behavioral testing was arranged so that the rats were tested on the RAM 1 day after drug administration followed by behavioral testing on the MWT 19 days after drug treatment, or tested on the MWT 1 day after drug administration followed by testing on the RAM4 days after drug treatment. Results of MWT testing showed that regardless of the drug/behavioral testing interval, lesioned rats given nicotine demonstrated enhancement relative to saline-treated animals. Results of RAM testing showed that nicotine improved performance in non-lesioned rats compared to non-lesioned rats given saline. Four days after drug administration, nicotine improved performance in lesioned rats to levels of non-lesioned rats regardless of drug treatment. A second experiment was implemented to determine if the previous training on the MWT affected performance on the RAM.
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