Date of Award
2007
Document Type
Dissertation
Publication Status
Version of Record
Submission Date
October 2026
Thesis/Dissertation Advisor [Chair]
Vertes, Robert P.
Abstract
The thalamus has been traditionally viewed as a structural relay to specific cortical areas behaviorally associated with sensory or motor functions, and thalamic nuclei that function in this manner are referred to as 'relay nuclei·. However. the parts of the thalamus interconnecting limbic association cortices (functionally involved in memory. reward, emotion. and decision making) comprise the midline and intralaminar nuclei. The midline thalamus has not been examined fully at the anatomical, physiological. or behavioral level, and may serve as an important relay between cortical and subcortical structures and the limbic system. The work incorporated into this dissertation included five axonal tract tracing projects that were conducted in the rat. to explore and test the hypothesis that the midline thalamus serves as an important interface between limbic structures including the amygdala. nucleus accumbens. medial prefrontal cortex and hippocampal formation. An important finding was the demonstration of a closed anatomical loop between the hippocampal formation, the ventral medial prefrontal cortex and the ventral midline thalamus: CA 1/subiculum > PLIIL > RE > CA 1/subiculum. Another finding was that 1) the hippocampal formation innervates the entire medial prefrontal cortex; and 2) the hippocampal formation projects more heavily to ventral as compared to dorsal cortices in the mPFC. The paraventricular, parataenial, rhomboid and reuniens nuclei of the midline thalamus were shown to distribute to limbic structures important for cognitive processing: the amygdala, nucleus accumbens, hippocampal formation, parahippocampal cortex, and the prefrontal cortex. Present results demonstrate that the ventral midline nuclei (reuniens and rhomboid) extensively innervate limbic cortical structures (the medial prefrontal cortex and hippocampal formation) whereas dorsal midline nuclei (paraventricular and parataenial) distribute more heavily to subcortical limbic structures (the amygdala and the nucleus accumbens). These midline nuclei may, therefore, relay information between these limbic areas. This connectivity suggests that the midline nuclei could further be subdivided from the intralaminar and relay groups. The midline thalamic nuclei would, therefore, comprise the limbic thalamus.
Extent
307 p.
Recommended Citation
Hoover, Walter Boyd III, "The Limbic Thalamus" (2007). Electronic Theses and Dissertations 2000 - 2009. 1370.
https://digitalcommons.fau.edu/etd_general_5/1370
Identifier
FA00000861
Comments
Includes bibliography.|Dissertation (Ph.D.)--Florida Atlantic University, 2007.|FAU Electronic Theses and Dissertations Collection|Charles E. Schmidt College of Science|Includes bibliography.