Abstract
Several species of insects have become model systems for studying learning and memory formation. Although many studies focus on freely moving animals, studies implementing classical conditioning paradigms with harnessed insects have been important for investigating the exact cues that individuals learn and the neural mechanisms underlying learning and memory formation. Here we present a protocol for evoking visual associative learning in wood ants through classical conditioning. In this paradigm, ants are harnessed and presented with a visual cue (a blue cardboard), the conditional stimulus (CS), paired with an appetitive sugar reward, the unconditional stimulus (US). Ants perform a Maxilla-Labium Extension Reflex (MaLER), the unconditional response (UR), which can be used as a readout for learning. Training consists of 10 trials, separated by a 5-minute intertrial interval (ITI). Ants are also tested for memory retention 10 minutes or 1 hour after training. This protocol has the potential to allow researchers to analyze, in a precise and controlled manner, the details of visual memory formation and the neural basis of learning and memory formation in wood ants.
Highlights
Insects have been extensively used as models for studying learning and memory formation[1]
The conditional stimulus (CS) must not induce a spontaneous response in the animals
The occurrence of MaxillaLabium Extension Reflex (MaLER) in response to the visual cue was significantly higher during paired than unpaired training, which was true for every trial except the first (Table 1)
Summary
Insects have been extensively used as models for studying learning and memory formation[1]. Recent studies have applied a similar approach to insects that do not have a proboscis, such as locusts, which perform the Palp Opening Response (POR)[12], and ants, which perform the Maxilla-Labium Extension Reflex (MaLER)[13] This has already revealed phase-specific learning abilities that match the phase-specific feeding strategies of the two different desert locust phenotypes, the gregarious and the solitarious forms, re-enforcing the idea that memory formation needs to match ecological needs[14]. Studies on olfactory learning in ants has shown similarities between ants and honeybees in memory formation and retention, with long-term memory retention, 72 hours after training, being dependent on protein synthesis[15] These adaptations of the original paradigm have allowed learning and memory formation to be studied with many modalities and in several model species. It is issued from our study of visual learning in wood ants[16], which is an adaptation of visual classical conditioning paradigms
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
