Learning, aging and intrinsic neuronal plasticity

• Published in: Trends in neurosciences (Regular ed.) Vol. 29; no. 10; pp. 587 - 599
• Main Authors: Disterhoft, John F., Oh, M. Matthew
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.10.2006; Elsevier Science; Elsevier Sequoia S.A
• Subjects: Aging; Animals; Biological and medical sciences; Brain; Brain - physiology; Central nervous system; Central neurotransmission. Neuromudulation. Pathways and receptors; Fundamental and applied biological sciences. Psychology; General aspects. Models. Methods; Humans; Learning; Learning - physiology; Membrane Potentials - physiology; Models, Neurological; Neuronal Plasticity - physiology; Neurons; Neurons - physiology; Vertebrates: nervous system and sense organs; Learning; Human; Spike; Acquisition process; Central nervous system; Synaptic plasticity; Excitability; Burst; Accommodation; Review; Pyramidal neuron; Encephalon
• ISSN: 0166-2236; 1878-108X
• DOI: 10.1016/j.tins.2006.08.005

In vitro experiments indicate that intrinsic neuronal excitability, as evidenced by changes in the post-burst afterhyperpolarization (AHP) and spike-frequency accommodation, is altered during learning and normal aging in the brain. Here we review these studies, highlighting two consistent findings: (i) that AHP and accommodation are reduced in pyramidal neurons from animals that have learned a task; and (ii) that AHP and accommodation are enhanced in pyramidal neurons from aging subjects, a cellular change that might contribute to age-related learning impairments. Findings from in vivo single-neuron recording studies complement the in vitro data. From these consistently reproduced findings, we propose that the intrinsic AHP level might determine the degree of synaptic plasticity and learning. Furthermore, it seems that reductions in the AHP must occur before learning if young and aging subjects are to learn a task successfully.