{"id":{"repo_id":"unr","oai_identifier":"oai:scholarwolf.unr.edu:11714/4531"},"canonical_url":"https://search.dev.ndltd.org/etd/unr/oai:scholarwolf.unr.edu:11714/4531","repository":{"repo_id":"unr","name":"University of Nevada - Reno","base_url":"https://scholarwolf.unr.edu/server/oai/request"},"display":{"title":"Quantitative Studies Defining the Cellular Composition of the Human Brain and Spinal Cord","abstract":"In 2009, a study using a new method, called the isotropic fractionator, challenged the long-standing \"common\" knowledge about the cellular composition of the human brain, by claiming a much lower glia neuron ratio. This study also asserted that glia numbered less than 80 billion, a drastic reduction from the several trillion glia cells previously presumed to be present in human brains. To assess the validity of these claims, I first tested in a series of calibration and validation experiments whether the isotropic fractionator (\"brain soup\" method) yielded data equivalent to the conventional, and already validated, histology/stereology methods. When I found that differences between the new and the older methods did not account for the discrepancies between conclusions, I then contributed to a systematic review of the literature to determine the source(s) of the incorrect information that had permeated all major textbooks and had been considered to be \"common knowledge.\" This work corrected 50 years of misinformation about the cellular composition of the human brain. Having clarified the cellular composition of the human brain, I then examined, for the first time quantitatively, the cellular composition of the human spinal cord and compared it with that of other vertebrate species to identify evolutionary trends.","abstract_html":"In 2009, a study using a new method, called the isotropic fractionator, challenged the long-standing "common" knowledge about the cellular composition of the human brain, by claiming a much lower glia neuron ratio. This study also asserted that glia numbered less than 80 billion, a drastic reduction from the several trillion glia cells previously presumed to be present in human brains. To assess the validity of these claims, I first tested in a series of calibration and validation experiments whether the isotropic fractionator ("brain soup" method) yielded data equivalent to the conventional, and already validated, histology/stereology methods. When I found that differences between the new and the older methods did not account for the discrepancies between conclusions, I then contributed to a systematic review of the literature to determine the source(s) of the incorrect information that had permeated all major textbooks and had been considered to be "common knowledge." This work corrected 50 years of misinformation about the cellular composition of the human brain. Having clarified the cellular composition of the human brain, I then examined, for the first time quantitatively, the cellular composition of the human spinal cord and compared it with that of other vertebrate species to identify evolutionary trends.","abstract_has_math":false,"creators":["Bahney, Jami"],"institution":null,"degree_name":null,"degree_level":"Doctorate Degree","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["von Bartheld, Christopher S."],"committee_chairs":[],"committee_members":["gould, thomas","smith, terrence","ward, sean","hutsler, jeffrey"],"year":2018,"date_issued":"2018","date_published":"2018","updated_at":"2026-07-27T21:47:47Z","subjects":[],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11714/4531","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["von Bartheld, Christopher S."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["gould, thomas","smith, terrence","ward, sean","hutsler, jeffrey"]},{"key":"dc:creator","label":"Author","values":["Bahney, Jami"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2018-09-13T16:10:21Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2018-09-13T16:10:21Z"]},{"key":"dc:date.issued","label":"Date","values":["2018"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Doctorate Degree"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11714/4531"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["In 2009, a study using a new method, called the isotropic fractionator, challenged the long-standing \"common\" knowledge about the cellular composition of the human brain, by claiming a much lower glia neuron ratio. This study also asserted that glia numbered less than 80 billion, a drastic reduction from the several trillion glia cells previously presumed to be present in human brains. To assess the validity of these claims, I first tested in a series of calibration and validation experiments whether the isotropic fractionator (\"brain soup\" method) yielded data equivalent to the conventional, and already validated, histology/stereology methods. When I found that differences between the new and the older methods did not account for the discrepancies between conclusions, I then contributed to a systematic review of the literature to determine the source(s) of the incorrect information that had permeated all major textbooks and had been considered to be \"common knowledge.\" This work corrected 50 years of misinformation about the cellular composition of the human brain. Having clarified the cellular composition of the human brain, I then examined, for the first time quantitatively, the cellular composition of the human spinal cord and compared it with that of other vertebrate species to identify evolutionary trends."]},{"key":"dc:format","label":"Dc Format","values":["PDF"]},{"key":"dc:title","label":"Title","values":["Quantitative Studies Defining the Cellular Composition of the Human Brain and Spinal Cord"]}]}],"canonical_facts":{"dc:contributor.advisor":["von Bartheld, Christopher S."],"dc:contributor.committeemember":["gould, thomas","smith, terrence","ward, sean","hutsler, jeffrey"],"dc:creator":["Bahney, Jami"],"dc:date.accessioned":["2018-09-13T16:10:21Z"],"dc:date.available":["2018-09-13T16:10:21Z"],"dc:date.issued":["2018"],"dc:description.abstract":["In 2009, a study using a new method, called the isotropic fractionator, challenged the long-standing \"common\" knowledge about the cellular composition of the human brain, by claiming a much lower glia neuron ratio. This study also asserted that glia numbered less than 80 billion, a drastic reduction from the several trillion glia cells previously presumed to be present in human brains. To assess the validity of these claims, I first tested in a series of calibration and validation experiments whether the isotropic fractionator (\"brain soup\" method) yielded data equivalent to the conventional, and already validated, histology/stereology methods. When I found that differences between the new and the older methods did not account for the discrepancies between conclusions, I then contributed to a systematic review of the literature to determine the source(s) of the incorrect information that had permeated all major textbooks and had been considered to be \"common knowledge.\" This work corrected 50 years of misinformation about the cellular composition of the human brain. Having clarified the cellular composition of the human brain, I then examined, for the first time quantitatively, the cellular composition of the human spinal cord and compared it with that of other vertebrate species to identify evolutionary trends."],"dc:format":["PDF"],"dc:identifier.uri":["http://hdl.handle.net/11714/4531"],"dc:title":["Quantitative Studies Defining the Cellular Composition of the Human Brain and Spinal Cord"],"dc:type":["Dissertation"],"thesis:degree_level":["Doctorate Degree"]},"updated_at":"2026-07-27T21:47:47Z"}