The effects of quisqualic acid lesions of the nucleus basalis magnocellularis on short-term memory capacities of the rat have been investigated using the delayed matching and non-matching to position tasks. The lesions do not disrupt performance of either task by pretrained animals, but do disrupt the ability to acquire the non-matching contingency, and to reverse to the non-matching task when trained on the matching task. The unidirectional nature of the reversal deficit has been replicated. The generalized disruption of performance of either task by the muscarinic antagonist scopolamine was comparable in lesioned and control rats. The lesions were associated with extensive loss of acetylcholinesterase staining in the basal forebrain and in the neocortex, and 55% depletions of choline acetyltransferase activity in the neocortex but not in the hippocampus. These observations demonstrate that the cholinergic projection from nucleus basalis to the neocortex is not critical for normal short-term memory, but that lesions involving this system do disrupt specific types of conditional discrimination learning.
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http://dx.doi.org/10.1111/j.1460-9568.1989.tb00804.x | DOI Listing |
J Neurol
December 2024
Cognitive and Motor Rehabilitation and Neuroimaging Unit, Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), Rome, Italy.
Prodromal Dementia with Lewy bodies (pro-DLB) has been recently defined; however, the neuroanatomical and functional correlates of this stage have not yet been univocally established. This study aimed to systematically review neuroimaging findings focused on pro-DLB. A literature search of works employing MRI, PET, and SPECT was performed.
View Article and Find Full Text PDFJ Neurol
December 2024
Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China.
Background: Free-water imaging can predict and monitor dopamine system degeneration in patients with Parkinson's disease (PD). However, brain cholinergic function has not been investigated to date in LRRK2 mutation carriers with or without PD using free-water imaging.
Objectives: To investigate the effect of LRRK2 mutations on the cholinergic system in manifest and premanifest stages of PD using free-water imaging.
J Comp Neurol
November 2024
Section on Circuits, Synapses, and Molecular Signaling, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA.
Cholinergic projection neurons of the nucleus basalis and substantia innominata (NBM/SI) densely innervate the basolateral amygdala (BLA) and have been shown to contribute to the encoding of fundamental and life-threatening experiences. Given the vital importance of these circuits in the acquisition and retention of memories that are essential for survival in a changing environment, it is not surprising that the basic anatomical organization of the NBM/SI is well conserved across animal classes as diverse as teleost and mammal. What is not known is the extent to which the physiology and morphology of NBM/SI neurons have also been conserved.
View Article and Find Full Text PDFbioRxiv
November 2024
Dept Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA.
Brain aging contributes to cognitive decline and risk of dementia. Degeneration of the basal forebrain cholinergic system parallels these changes in aging, Alzheimer's dementia, Parkinson's dementia, and Lewy body dementia, and thus is a common element linked to executive function across the lifespan and in disease states. Here, we tested the potential of one-hour daily intermittent basal forebrain stimulation to improve cognition in senescent monkeys, and its mechanisms of action.
View Article and Find Full Text PDFJ Neurochem
November 2024
Department of Neurology, RWTH Aachen University, Aachen, Germany.
Parkinson's disease (PD) is the second-fastest growing neurodegenerative disease in the world. The major clinical symptoms rigor, tremor, and bradykinesia derive from the degeneration of the nigrostriatal pathway. However, PD is a multi-system disease, and neurodegeneration extends beyond the degradation of the dopaminergic pathway.
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