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Previous research looking at expectancy in animals has used various experimental designs focusing on appetitive and avoidance behaviors. In this study, honey bees (Apis mellifera) were tested ina series of three proboscis extension response (PER) experiments to determine to what degree honey bees’ form a cognitive-representation of an unconditioned stimulus (US). Tthe first experiment, bees were presented with either a 2 sec. sucrose US or 2 sec. honey US appetitive reward and the proboscis-extension duration was measured under each scenario. The PER duration was longer for the honey US even though each US was presented for just 2 sec. Honey bees in the second experiment were tested during extinction trials on a conditioned stimulus (CS) of cinnamon or lavender that was paired with either the sucrose US or honey US in the acquisition trials. The proportion of bees showing the PER response to the CS was recorded for each extinction trial for each US scenario, as was the duration of the proboscis extension for each bee. Neither measure differed between the honey US and sucrose US scenarios, In experiment three, bees were presented with a cinnamon or lavender CS paired with either honey US or sucrose US in a set of acquisition trials, but here the US was not given until after the proboscis was retracted. The PER duration after the CS, and again subsequent after the US, were recorded. While the PER duration after the US was longer for honey, the PER duration after the CS did not differ between honey US and sucrose US.
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Observing a trained demonstrator influences associative appetitive learning in rats
The ability to acquire information about the environment through social observation or instruction is an essential form of learning in humans and other animals. Here, we assessed the ability of rats to acquire an association between a light stimulus and the presentation of a reward that is either hidden (sucrose solution) or visible (food pellet) via observation of a trained demonstrator. Subsequent training of observers on the light-reward association indicated that while observation alone was not sufficient for observers to acquire the association, contact with the reward location was higher in observers that were paired with a demonstrator. However, this was only true when the light cue predicted a sucrose reward. Additionally, we found that in the visible reward condition, levels of demonstrator orienting and food cup contact during the observation period tended to be positively correlated with the corresponding behaviour of their observer. This relationship was only seen during later sessions of observer training. Together, these results suggest that while our models were not sufficient to induce associative learning through observation alone, demonstrator behaviour during observation did influence how their paired observer's behavioural response to the cue evolved over the course of direct individual training.
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- Award ID(s):
- 2141102
- PAR ID:
- 10413721
- Date Published:
- Journal Name:
- Royal Society Open Science
- Volume:
- 10
- Issue:
- 4
- ISSN:
- 2054-5703
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1098/rsos.221224
