Journal article
Developmental changes in hippocampal associative coding
The Journal of neuroscience, Vol.35(10), pp.4238-4247
03/11/2015
DOI: 10.1523/JNEUROSCI.3145-14.2015
PMCID: PMC4355197
PMID: 25762670
Abstract
Behavioral analyses of the ontogeny of memory have shown that hippocampus-dependent learning emerges relatively late in postnatal development compared with simple associative learning. Maturation of hippocampal mnemonic mechanisms has been hypothesized to underlie the development of the later emerging learning processes. However, the role of hippocampal maturation in learning has not been examined directly. The goal of the present study was to examine developmental changes in hippocampal neuronal coding during acquisition of a hippocampus-dependent learning task. We recorded activity from CA1 pyramidal cells in rat pups while they were trained on trace eyeblink conditioning. Trace eyeblink conditioning is a Pavlovian conditioning task that involves the association of a conditioned stimulus (CS) with an unconditioned stimulus over a stimulus-free trace interval. The inclusion of the trace interval is what makes the task hippocampus dependent. In the present study, rats were trained at 21-23, 24-26, and 31-33 d of age. Previous research from our laboratory and others shows that trace conditioning begins to emerge during the third postnatal week. The results indicate that hippocampal neurons show a substantial increase in responsiveness to task-relevant events during development. Moreover, there is an age-related increase in the proportion of neurons that respond to a combination of trial events (e.g., CS and trace). Our findings indicate that the developmental emergence of hippocampally mediated learning is related to increases in the strength and complexity of CA1 associative coding.
Details
- Title: Subtitle
- Developmental changes in hippocampal associative coding
- Creators
- Mary E Goldsberry - Department of Psychology, University of Iowa, Iowa City, Iowa 52242Jangjin Kim - Department of Psychology, University of Iowa, Iowa City, Iowa 52242John H Freeman - Department of Psychology, University of Iowa, Iowa City, Iowa 52242 john-freeman@uiowa.edu
- Resource Type
- Journal article
- Publication Details
- The Journal of neuroscience, Vol.35(10), pp.4238-4247
- Publisher
- United States
- DOI
- 10.1523/JNEUROSCI.3145-14.2015
- PMID
- 25762670
- PMCID
- PMC4355197
- ISSN
- 0270-6474
- eISSN
- 1529-2401
- Grant note
- NS038890 / NINDS NIH HHS R01 NS038890 / NINDS NIH HHS
- Language
- English
- Date published
- 03/11/2015
- Academic Unit
- Psychological and Brain Sciences; Iowa Neuroscience Institute
- Record Identifier
- 9984065861702771
Metrics
11 Record Views