PT  - JOURNAL ARTICLE
AU  - Benedetta Leuner
AU  - Jaylyn Waddell
AU  - Elizabeth Gould
AU  - Tracey J. Shors
TI  - Temporal Discontiguity Is neither Necessary nor Sufficient for Learning-Induced Effects on Adult Neurogenesis
AID  - 10.1523/JNEUROSCI.2781-06.2006
DP  - 2006 Dec 27
TA  - The Journal of Neuroscience
PG  - 13437--13442
VI  - 26
IP  - 52
4099  - http://www.jneurosci.org/content/26/52/13437.short
4100  - http://www.jneurosci.org/content/26/52/13437.full
SO  - J. Neurosci.2006 Dec 27; 26
AB  - Some, but not all, types of learning and memory can influence neurogenesis in the adult hippocampus. Trace eyeblink conditioning has been shown to enhance the survival of new neurons, whereas delay eyeblink conditioning has no such effect. The key difference between the two training procedures is that the conditioning stimuli are separated in time during trace but not delay conditioning. These findings raise the question of whether temporal discontiguity is necessary for enhancing the survival of new neurons. Here we used two approaches to test this hypothesis. First, we examined the influence of a delay conditioning task in which the duration of the conditioned stimulus (CS) was increased nearly twofold, a procedure that critically engages the hippocampus. Although the CS and unconditioned stimulus are contiguous, this very long delay conditioning procedure increased the number of new neurons that survived. Second, we examined the influence of learning the trace conditioned response (CR) after having acquired the CR during delay conditioning, a procedure that renders trace conditioning hippocampal-independent. In this case, trace conditioning did not enhance the survival of new neurons. Together, these results demonstrate that associative learning increases the survival of new neurons in the adult hippocampus, regardless of temporal contiguity.