title: Molecular mechanisms of memory in imprinting.
abstract: Converging evidence implicates the intermediate and medial mesopallium (IMM) of the domestic chick forebrain in memory for a visual imprinting stimulus. During and after imprinting training, neuronal responsiveness in the IMM to the familiar stimulus exhibits a distinct temporal profile, suggesting several memory phases. We discuss the temporal progression of learning-related biochemical changes in the IMM, relative to the start of this electrophysiological profile. c-fos gene expression increases <15 min after training onset, followed by a learning-related increase in Fos expression, in neurons immunopositive for GABA, taurine and parvalbumin (not calbindin). Approximately simultaneously or shortly after, there are increases in phosphorylation level of glutamate (AMPA) receptor subunits and in releasable neurotransmitter pools of GABA and taurine. Later, the mean area of spine synapse post-synaptic densities, N-methyl-D-aspartate receptor number and phosphorylation level of further synaptic proteins are elevated. After ∼ 15 h, learning-related changes in amounts of several synaptic proteins are observed. The results indicate progression from transient/labile to trophic synaptic modification, culminating in stable recognition memory.
authors.affiliation: Institute of Chemical Biology, Ilia State University, 3/5 K Cholokashvili Av, Tbilisi 0162, Georgia; I. Beritashvili Centre of Experimental Biomedicine, Tbilisi, Georgia. Electronic address: revaz_solomonia@iliauni.edu.ge.
authors.forename: Revaz O
authors.initials: RO
authors.lastname: Solomonia
authors.affiliation: University of Cambridge, Department of Zoology, Sub-Department of Animal Behaviour, Madingley, Cambridge CB23 8AA, United Kingdom. Electronic address: bjm1@cam.ac.uk.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: McCabe
mesh_terms: D000818:Animals; D002645:Chickens; D007173:Imprinting, Psychological / Q000502:physiology*; D008568:Memory / Q000502:physiology*; D051379:Mice; D009474:Neurons / Q000378:metabolism*; D016548:Prosencephalon / Q000502:physiology*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D018091:Receptors, AMPA / Q000378:metabolism; D015398:Signal Transduction; D013569:Synapses / Q000378:metabolism / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D018091:Receptors, AMPA; D005680:gamma-Aminobutyric Acid
keywords: Behavioural imprinting; IMM; Learning; Memory