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Pontomesencephalic tegmental cholinergic neurons were destroyed in cats by local injections of kainic acid in order to assess the role of these neurons in sleep-wakefulness states and in the defining variables of these states: EEG (electroencephalographic) and EMG (electromyographic) amplitude, PGO (ponto-geniculo-occipital) spike rate, REMs (rapid eye movements) and (OBS) olfactory bulb spindles. Loss of cholinergic innervation to forebrain and brainstem structures was also assessed by histochemistry. Histological and histochemical analysis of the brains after the lesion showed a major destruction of the pontomesencephalic cholinergic neurons and a major loss of innervation to thalamic nuclei and brainstem regions, including the reticular formation. Whereas the states of waking and slow wave sleep were relatively unaffected, paradoxical sleep (PS) was reduced or eliminated immediately following the lesions. Two to three weeks later, incipient PS-like episodes returned with a reduced PGO spike rate and REMs, and an elevated EMG amplitude, marking the loss of muscle atonia. Such results suggest pontomesencephalic cholinergic neurons and their projections to thalamic and brainstem regions are important for the expression of PS and its defining variables.

To date, research using rodent models has primarily dealt with the visual aspects of attention, while in the present research, we examined neurochemical modulation of attentional processes using both a visual and an olfactory five choice serial reaction time task (5-CSRTT). The nucleus basalis magnocellularis (NBM) in the basal forebrain is the primary source of cortical cholinergic input, which is thought to have an important modulatory effect on rat attentional processes. Thus, after successful acquisition of the task, the rats were subjected to either a cholinergic immunotoxic or sham lesion surgery of the NBM. Cortical cholinergic deafferentation of the cortical mantle was induced by bilaterally infusing 0.2 µg/µl of the cholinergic immunotoxin, 192 IgG-saporin, into the NBM (saporin-lesion). Reduction of cortical cholinergic modulation led to comparable attentional impairments in the saporin-lesion group, relative to the sham-lesioned group, on both visual and olfactory versions of the 5-CSRTT.

To date, research using rodent models has primarily dealt with the visual aspects of attention, while in the present research, we examined neurochemical modulation of attentional processes using both a visual and an olfactory five choice serial reaction time task (5-CSRTT). The nucleus basalis magnocellularis (NBM) in the basal forebrain is the primary source of cortical cholinergic input, which is thought to have an important modulatory effect on rat attentional processes. Thus, after successful acquisition of the task, the rats were subjected to either a cholinergic immunotoxic or sham lesion surgery of the NBM. Cortical cholinergic deafferentation of the cortical mantle was induced by bilaterally infusing 0.2 µg/µl of the cholinergic immunotoxin, 192 IgG-saporin, into the NBM (saporin-lesion). Reduction of cortical cholinergic modulation led to comparable attentional impairments in the saporin-lesion group, relative to the sham-lesioned group, on both visual and olfactory versions of the 5-CSRTT.

Errata is tipped in between leaf 9 & 10. / Bibliography: leaves 209-235. / 235 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Focusses specifically on the role of acetylcholine in the circadian timing system of mammals, using the rat as an animal model. / Thesis (Ph.D.)--University of Adelaide, Dept. of Obstetrics and Gynaecology, 1999

Thesis (M.S.)--Brigham Young University. Dept. of Physiology and Developmental Biology, 2006. / Includes bibliographical references (p. 47-50).

Thesis (Ph.D.)--Tufts University, 2003. / Adviser: Barry A. Trimmer. Submitted to the Dept. of Biology. Includes bibliographical references (leaves 165-178). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Diss. (sammanfattning) Stockholm : Karol. inst., 2001. / Härtill 5 uppsatser.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 72-87). Also available via the Internet.

Thesis (Ph.D.)--Biology, Georgia Institute of Technology, 2008. / Committee Chair: Dr. Nael A. McCarty; Committee Co-Chair: Dr. Darrell Jackson; Committee Member: Dr. Alfred H. Merrill; Committee Member: Dr. Barbara D. Boyan; Committee Member: Dr. Harish Radhakrishna; Committee Member: Dr. Marion B. Sewer