Stimulus-food pairings produce stimulus-directed touch-screen responding in cynomolgus monkeys (macaca fascicularis) with or without a positive response contingency

Abstract

Acquisition and maintenance of touch-screen responding was examined in naïve cynomolgus monkeys (Macaca fascicularis) under automaintenance and classical conditioning arrangements. In the first condition of Experiment 1, we compared acquisition of screen touching to a randomly positioned stimulus (a gray square) that was either stationary or moving under automaintenance (i.e., banana pellet delivery followed an 8-s stimulus presentation or immediately upon a stimulus touch). For all subjects stimulus touching occurred within the first session and increased to at least 50% of trials by the end of four sessions (320 trials). In the subsequent condition, stimulus touching further increased under a similar procedure in which pellets were only delivered if a stimulus touch occurred (fixed ratio 1 with 8-s limited hold). In Experiment 2, 6 naive subjects were initially exposed to a classical conditioning procedure (8-s stimulus preceded pellet delivery). Despite the absence of a programmed response contingency, all subjects touched the stimulus within the first session and responded on about 50% or more of trials by the second session. Responding was also sensitive to negative, neutral, and positive response contingencies introduced in subsequent conditions. Similar to other species, monkeys engaged in stimulus-directed behavior when stimulus presentations were paired with food delivery. However, stimulus-directed behavior quickly conformed to response contingencies upon subsequent introduction. Video recordings of sessions showed topographies of stimulus-directed behavior that resembled food acquisition and consumption.

Keywords: automaintenance; autoshaping; monkey; negative automaintenance; response acquisition; touch screen.

Fig 1

Proportion of stimulus presentations during which at least one stimulus touch occurred in Experiment 1 plotted as a function of session and conditions. Vertical dashed line separates the positive automaintenance (PAM) condition from the subsequent FR1 with 8-s limited hold.

Fig 2

Cumulative number of trials with at least one stimulus touch plotted as a function of the first (dashed lines) and last (solid lines) sessions of the first stimulus-pairing condition in Experiment 2.

Fig 3

Proportion of stimulus presentations during which at least one stimulus touch occurred in Experiment 2 plotted as a function of session and conditions. Vertical dashed lines denote condition changes from stimulus pairing (SP), negative automaintanence (NAM), conjunctive Fixed-Ratio 1 Fixed-Time 8 s, and Fixed Ratio 1 with an 8-s limited hold.

Fig 4

Average number of on-stimulus (open circles) and off-stimulus (closed circles) touches that occurred during 8-s stimulus presentations for all sessions of the first four conditions of Experiment 2 (stimulus pairing [SP], negative automaintanence [NAM], conjunctive Fixed-Ratio 1 Fixed-Time 8 s).

Fig 5

Cumulative number of on- and off-stimulus touches during 8-s stimulus presentations (preceding pellet delivery) as a function of the obtained response–pellet delay, collapsed across the last two sessions (160 trials) of the first four conditions from Experiment 2 (stimulus pairing [SP], negative automaintenance [NAM], conjunctive Fixed-Ratio 1 Fixed-Time 8 s).

Fig 6

Cumulative number of screen touches occurring during 8-s stimulus presentations as a function of distance from the stimulus center. Data are collapsed across the last two sessions of the first four conditions from Experiment 2, with each condition denoted by different symbols (stimulus pairing [SP], negative automaintenance [NAM], conjunctive Fixed-Ratio 1 Fixed-Time 8 s). Data points left of the vertical dashed lines denote on-stimulus touches.

Fig 7

Pictures of representative stimulus–touch response topographies for each of 3 monkeys from Experiment 2.