Transfer between anticipatory and consummatory tasks involving reward loss

Partial reinforcement in rat autoshaping with a long CS: Effects of pramipexole and chlordiazepoxide on sign and goal tracking

“…The same comparison would suggest 10 lever presses per trial in the present experiment, but only 5-6 lever presses per trial for CR animals in Torres et al's (2016) experiment. Second, the PRAE has not been always reported in rat autoshaping (Boughner & Papini, 2008), but it has also been found in several experiments (Boakes, 1977;Anselme et al, 2013;Robinson et al, 2014;Torres et al, 2016;Glueck et al, 2018). This suggests that the PRAE is a replicable phenomenon in autoshaping and that its absence in the present experiment should not reflect the absence of an effect of uncertainty on performance.…”

“…Rats are said to sign track when they interact (press, nibble, and sniff) with the lever during its presentation, while they are said to goal track when they instead approach and inspect the magazine where food is to be delivered after the lever is retracted. In autoshaping with rats, the unpredictable delivery of food after a lever presentation (partial reinforcement, PR) tends to increase sign-tracking responses compared to the predictable delivery of food on each trial (continuous reinforcement, CR; Anselme, Robinson, & Berridge, 2013;Boakes, 1977;Glueck, Torres, & Papini, 2018;Robinson, Anselme, Fischer, & Berridge, 2014;Torres, Glueck, Conrad, Morón, & Papini, 2016). This result resembles the partial reinforcement acquisition effect (PRAE) reported in runways, where rats run faster in the early segment of a runway under PR than under CR (Goodrich, 1959;Haggard, 1959).…”

“…Separating the two phenotypes was here not possible given the limited sample size in each group. However, the PR vs. CR effects are typically reported in undifferentiated groups of rats (e.g., Boakes, 1977;Glueck et al, 2018;Robinson, Anselme, Fischer, & Berridge, 2014). We studied sign-and goal-tracking behaviors separately within the same individuals to determine whether competition-induced symmetrical effects in behavioral expression could be observed (Boakes, 1977)…”

Decreased Key Pecking in Response to Reward Uncertainty and Surprising Delay Extension in Pigeons

“…While trace conditioning is ineffective in producing a conditioned response, filling the gap between the CS and the UCS is known to boost excitatory conditioning (Kaplan & Hearst, 1982;Rescorla, 1980). This finding contrasts with the well-established evidence that rats increase their response ratesmeasured as lever pressing and lever nibbling -to an uncertain CS relative to a certain CS (Anselme et al, 2013;Glueck et al, 2018;Hellberg et al, 2018;Robinson et al, 2014;Torres et al, 2016), even though this effect sometimes fails to occur (Boughner & Papini, 2008;Russell & Robinson, 2019). The procedure with rats is slightly different from that used here (only one CS is presented), and pigeons have been shown to increase their responses using the rat procedure (Gottlieb, 2004;Perkins et al, 1975).…”

“…One of them consists of repeatedly exposing organisms to reward uncertainty in Pavlovian autoshaping, a procedure in which the brief presentation of a conditioned stimulus (CS; lever insertion in rats or key illumination in pigeons) randomly predicts the delivery of food or nothing. In rats, reward uncertainty typically enhances sign-tracking (CSdirected) responses in comparison with reward certainty, where each CS presentation is food rewarded (Anselme et al, 2013;Glueck et al, 2018;Hellberg et al, 2018;Robinson et al, 2014;Torres et al, 2016). Under conditions of reward certainty, sign-tracking is both a product of associative learning (the rat has to learn that the CS predicts food) and incentive salience, a dopamine-dependent brain process that makes the CS motivationally attractive (i.e., approached, sniffed, nibbled, and pressed;Berridge, 2007).…”