자료유형  

 학위논문

Control Number  

0016931276

International Standard Book Number  

9798380620581

Dewey Decimal Classification Number  

616

Main Entry-Personal Name  

Mukerji, Arjun.

Publication, Distribution, etc. (Imprint  

[S.l.] : University of California, Berkeley., 2022

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2022

Physical Description  

1 online resource(59 p.)

General Note  

Source: Dissertations Abstracts International, Volume: 85-04, Section: B.

General Note  

Advisor: Silver, Michael A.

Dissertation Note  

Thesis (Ph.D.)--University of California, Berkeley, 2022.

Restrictions on Access Note  

This item must not be sold to any third party vendors.

Summary, Etc.  

요약Anatomical, physiological, and psychophysical approaches have revealed a great deal about the structure and function of the visual system. Non-invasive techniques based on nuclear magnetic resonance supplement these approaches by allowing the possibility of recording from the awake, behaving human brain. Here, we present two experiments using different non-invasive techniques to answer questions about the neural basis of human vision. In Chapter 2, we examine the relationship between γ-aminobutyric acid (GABA), perceptual suppression, and amblyopia ("lazy eye"). In amblyopia, abnormal visual experience during development leads to an enduring loss of visual acuity in adulthood. Physiological studies in animal models suggest that intracortical GABAergic inhibition may mediate visual deficits in amblyopia. To better understand the relationship between visual cortical GABA and perceptual suppression in persons with amblyopia (PWA), we employed magnetic resonance spectroscopy (MRS) to quantify GABA levels in both PWA and normally-sighted persons (NSP). In the same individuals, we obtained psychophysical measures of perceptual suppression for a variety of ocular configurations. In PWA, we found a robust negative correlation between the depth of amblyopia (the difference in visual acuity between the amblyopic and non-amblyopic eyes) and GABA concentration that was specific to visual cortex and was not observed in a sensorimotor cortical control region. Moreover, lower levels of visual cortical GABA were associated with weaker perceptual suppression of the fellow eye by the amblyopic eye and stronger suppression of the amblyopic eye by the fellow eye. Taken together, our findings provide evidence that intracortical GABAergic inhibition is an important component of the pathology of human amblyopia and suggest possible therapeutic interventions to restore vision in the amblyopic eye through enhancement of visual cortical GABAergic signaling in PWA.In Chapter 3, we use functional magnetic resonance imaging (fMRI) to identify cortical and subcortical components of the visual system. In particular, we localized many topographically-organized visual cortical areas as well as the lateral geniculate nucleus (LGN) and the magnocellular and parvocellular subdivisions thereof. We report the extension of this M/P localization procedure to fMRI data acquired with multiband acceleration. We also examined thalamocortical coupling between the LGN subdivisions and visual cortical areas but found no effects of stimulus type or spatial attention.

Subject Added Entry-Topical Term  

Neurosciences.

Subject Added Entry-Topical Term  

Physiology.

Subject Added Entry-Topical Term  

Psychobiology.

Subject Added Entry-Topical Term  

Medical imaging.

Index Term-Uncontrolled  

Human brain

Index Term-Uncontrolled  

Magnetic resonance spectroscopy

Index Term-Uncontrolled  

Amblyopia

Index Term-Uncontrolled  

Perceptual suppression

Index Term-Uncontrolled  

Functional magnetic resonance imaging

Added Entry-Corporate Name  

University of California, Berkeley Neuroscience

Host Item Entry  

Dissertations Abstracts International. 85-04B.

Host Item Entry  

Dissertation Abstract International

Electronic Location and Access  

로그인을 한후 보실 수 있는 자료입니다.

Control Number  

joongbu:641425