Reward Value Determines Memory Consolidation in Parasitic Wasps

TY - JOUR

T1 - Reward Value Determines Memory Consolidation in Parasitic Wasps

AU - Kruidhof, H.M.

AU - Pashalidou, F.

AU - Fatouros, N.E.

AU - Figueroa, I.A.

AU - Vet, L.E.M.

AU - Smid, H.M.

AU - Huigens, M.E.

N1 - Reporting year: 2012 Metis note: 5398; Wag; TE; L:\EndnoteDatabases\NIOOPUB\pdfs\PDFS2012\Kruidhof_ea_5398.pdf <Go to ISI>://WOS:000308286300002

PY - 2012

Y1 - 2012

N2 - Animals can store learned information in their brains through a series of distinct memory forms. Short-lasting memory forms can be followed by longer-lasting, consolidated memory forms. However, the factors determining variation in memory consolidation encountered in nature have thus far not been fully elucidated. Here, we show that two parasitic wasp species belonging to different families, Cotesia glomerata (Hymenoptera: Braconidae) and Trichogramma evanescens (Hymenoptera; Trichogrammatidae), similarly adjust the memory form they consolidate to a fitness-determining reward: egg-laying into a host-insect that serves as food for their offspring. Protein synthesis-dependent long-term memory (LTM) was consolidated after single-trial conditioning with a high-value host. However, single-trial conditioning with a low-value host induced consolidation of a shorter-lasting memory form. For Cotesia glomerata, we subsequently identified this shorter-lasting memory form as anesthesia-resistant memory (ARM) because it was not sensitive to protein synthesis inhibitors or anesthesia. Associative conditioning using a single reward of different value thus induced a physiologically different mechanism of memory formation in this species. We conclude that the memory form that is consolidated does not only change in response to relatively large differences in conditioning, such as the number and type of conditioning trials, but is also sensitive to more subtle differences, such as reward value. Reward-dependent consolidation of exclusive ARM or LTM provides excellent opportunities for within-species comparison of mechanisms underlying memory consolidation. [KEYWORDS: long-term-memory trichogramma wasps cotesia-glomerata protein-synthesis natural variation apis-mellifera learning rate c-rubecula drosophila quality]

AB - Animals can store learned information in their brains through a series of distinct memory forms. Short-lasting memory forms can be followed by longer-lasting, consolidated memory forms. However, the factors determining variation in memory consolidation encountered in nature have thus far not been fully elucidated. Here, we show that two parasitic wasp species belonging to different families, Cotesia glomerata (Hymenoptera: Braconidae) and Trichogramma evanescens (Hymenoptera; Trichogrammatidae), similarly adjust the memory form they consolidate to a fitness-determining reward: egg-laying into a host-insect that serves as food for their offspring. Protein synthesis-dependent long-term memory (LTM) was consolidated after single-trial conditioning with a high-value host. However, single-trial conditioning with a low-value host induced consolidation of a shorter-lasting memory form. For Cotesia glomerata, we subsequently identified this shorter-lasting memory form as anesthesia-resistant memory (ARM) because it was not sensitive to protein synthesis inhibitors or anesthesia. Associative conditioning using a single reward of different value thus induced a physiologically different mechanism of memory formation in this species. We conclude that the memory form that is consolidated does not only change in response to relatively large differences in conditioning, such as the number and type of conditioning trials, but is also sensitive to more subtle differences, such as reward value. Reward-dependent consolidation of exclusive ARM or LTM provides excellent opportunities for within-species comparison of mechanisms underlying memory consolidation. [KEYWORDS: long-term-memory trichogramma wasps cotesia-glomerata protein-synthesis natural variation apis-mellifera learning rate c-rubecula drosophila quality]

KW - national

U2 - 10.1371/journal.pone.0039615

DO - 10.1371/journal.pone.0039615

M3 - Article

SN - 1932-6203

VL - 7

JO - PLoS One

JF - PLoS One

IS - 8

M1 - e39615

ER -