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The form of a conditioned stimulus can influence the degree to which it acquires incentive motivational properties.

Meyer PJ, Cogan ES, Robinson TE - PLoS ONE (2014)

Bottom Line: There is considerable individual variation in the extent to which food- and drug-associated cues (conditioned stimuli, CSs) acquire incentive salience, as indicated by whether they elicit approach towards them, and/or act as conditioned reinforcers.Even when presented in compound (a lever-tone CS), the two elements of the compound differentially acquired motivational properties.We conclude that variation in the to the ability of CSs to acquire incentive salience, and thus their ability to act as incentive stimuli capable of motivating behavior, is determined in part by properties of the CS itself.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Michigan, Ann Arbor, Michigan, United States of America.

ABSTRACT
There is considerable individual variation in the extent to which food- and drug-associated cues (conditioned stimuli, CSs) acquire incentive salience, as indicated by whether they elicit approach towards them, and/or act as conditioned reinforcers. Here we asked whether this variation is influenced by properties of the CS itself. In rats, we assessed both the attractiveness and conditioned reinforcing properties of two CSs: a manipulable lever CS versus an auditory (tone) CS. There was considerable individual variation in the extent to which a lever CS acquired incentive motivational properties, as indicated by whether it became attractive (evoked a sign-tracking or goal-tracking conditioned response) or acted as a conditioned reinforcer. However, with a tone CS all rats learned a goal-tracking response, and the tone CS was an equally effective conditioned reinforcer in sign-trackers and goal-trackers. Even when presented in compound (a lever-tone CS), the two elements of the compound differentially acquired motivational properties. In contrast, amphetamine and stress potentiated the conditioned reinforcing properties of both visual and auditory CSs similarly in rats that primarily sign-tracked or goal-tracked. We conclude that variation in the to the ability of CSs to acquire incentive salience, and thus their ability to act as incentive stimuli capable of motivating behavior, is determined in part by properties of the CS itself.

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Related in: MedlinePlus

Proximal auditory stimuli (either tone or white noise) are more reinforcing than distal stimuli.Rats made more food-cup entries during the proximal stimulus presentation during training (panel A), and performed more nose-pokes for the proximal stimulus (panel B). Data are represented as mean (± SEM). There were no significant differences between sign-trackers (ST) and goal-trackers (GT).
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pone-0098163-g005: Proximal auditory stimuli (either tone or white noise) are more reinforcing than distal stimuli.Rats made more food-cup entries during the proximal stimulus presentation during training (panel A), and performed more nose-pokes for the proximal stimulus (panel B). Data are represented as mean (± SEM). There were no significant differences between sign-trackers (ST) and goal-trackers (GT).

Mentions: Out of 42 rats tested during PCA, 16 STs, 10 GTs, and 16 INs were identified as described in Exp. 1. As expected, when sequential auditory CSs were paired with food-pellet delivery, rats entered the magazine more during the proximal CS compared to the distal CS [Fig 5A; F (1, 20) = 11.1, p<0.01 for the main effect of Interval]. There were no significant differences between STs and GTs (p>0.05). This demonstrates that rats enter the magazine more during the proximal stimulus than the distal stimulus. This is probably because rats had already approached and entered the food magazine by the time the proximal stimulus was presented. Therefore, the important tests of whether the distal and proximal CSs differentially acquired motivational properties are the conditioned reinforcement tests, which were given subsequent to the Pavlovian conditioning sessions. For the conditioned reinforcement test, rats responded significantly more for the proximal stimulus, relative to the distal stimulus [Fig 5B; F = (1, 20); 9.0, p<0.01 for the main effect of Interval], which indicates that the proximal stimulus was more reinforcing. Compared to GTs, STs had elevated responding over all [F (1,20) = 9.2; p<0.01 for the main effect of Phenotype]. However, this effect did not interact with Interval (p>0.05), which indicates that that STs did not respond more for the distal or proximal CSs than GTs. Thus, it does not appear that STs and GTs make associations between different temporal components of an auditory CS and US.


The form of a conditioned stimulus can influence the degree to which it acquires incentive motivational properties.

Meyer PJ, Cogan ES, Robinson TE - PLoS ONE (2014)

Proximal auditory stimuli (either tone or white noise) are more reinforcing than distal stimuli.Rats made more food-cup entries during the proximal stimulus presentation during training (panel A), and performed more nose-pokes for the proximal stimulus (panel B). Data are represented as mean (± SEM). There were no significant differences between sign-trackers (ST) and goal-trackers (GT).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4048203&req=5

pone-0098163-g005: Proximal auditory stimuli (either tone or white noise) are more reinforcing than distal stimuli.Rats made more food-cup entries during the proximal stimulus presentation during training (panel A), and performed more nose-pokes for the proximal stimulus (panel B). Data are represented as mean (± SEM). There were no significant differences between sign-trackers (ST) and goal-trackers (GT).
Mentions: Out of 42 rats tested during PCA, 16 STs, 10 GTs, and 16 INs were identified as described in Exp. 1. As expected, when sequential auditory CSs were paired with food-pellet delivery, rats entered the magazine more during the proximal CS compared to the distal CS [Fig 5A; F (1, 20) = 11.1, p<0.01 for the main effect of Interval]. There were no significant differences between STs and GTs (p>0.05). This demonstrates that rats enter the magazine more during the proximal stimulus than the distal stimulus. This is probably because rats had already approached and entered the food magazine by the time the proximal stimulus was presented. Therefore, the important tests of whether the distal and proximal CSs differentially acquired motivational properties are the conditioned reinforcement tests, which were given subsequent to the Pavlovian conditioning sessions. For the conditioned reinforcement test, rats responded significantly more for the proximal stimulus, relative to the distal stimulus [Fig 5B; F = (1, 20); 9.0, p<0.01 for the main effect of Interval], which indicates that the proximal stimulus was more reinforcing. Compared to GTs, STs had elevated responding over all [F (1,20) = 9.2; p<0.01 for the main effect of Phenotype]. However, this effect did not interact with Interval (p>0.05), which indicates that that STs did not respond more for the distal or proximal CSs than GTs. Thus, it does not appear that STs and GTs make associations between different temporal components of an auditory CS and US.

Bottom Line: There is considerable individual variation in the extent to which food- and drug-associated cues (conditioned stimuli, CSs) acquire incentive salience, as indicated by whether they elicit approach towards them, and/or act as conditioned reinforcers.Even when presented in compound (a lever-tone CS), the two elements of the compound differentially acquired motivational properties.We conclude that variation in the to the ability of CSs to acquire incentive salience, and thus their ability to act as incentive stimuli capable of motivating behavior, is determined in part by properties of the CS itself.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Michigan, Ann Arbor, Michigan, United States of America.

ABSTRACT
There is considerable individual variation in the extent to which food- and drug-associated cues (conditioned stimuli, CSs) acquire incentive salience, as indicated by whether they elicit approach towards them, and/or act as conditioned reinforcers. Here we asked whether this variation is influenced by properties of the CS itself. In rats, we assessed both the attractiveness and conditioned reinforcing properties of two CSs: a manipulable lever CS versus an auditory (tone) CS. There was considerable individual variation in the extent to which a lever CS acquired incentive motivational properties, as indicated by whether it became attractive (evoked a sign-tracking or goal-tracking conditioned response) or acted as a conditioned reinforcer. However, with a tone CS all rats learned a goal-tracking response, and the tone CS was an equally effective conditioned reinforcer in sign-trackers and goal-trackers. Even when presented in compound (a lever-tone CS), the two elements of the compound differentially acquired motivational properties. In contrast, amphetamine and stress potentiated the conditioned reinforcing properties of both visual and auditory CSs similarly in rats that primarily sign-tracked or goal-tracked. We conclude that variation in the to the ability of CSs to acquire incentive salience, and thus their ability to act as incentive stimuli capable of motivating behavior, is determined in part by properties of the CS itself.

Show MeSH
Related in: MedlinePlus