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- Genre: Doctoral Dissertation
Description
Timing performance is sensitive to fluctuations in time and motivation, thus interval timing and motivation are either inseparable or conflated processes. A behavioral systems model (e.g., Timberlake, 2000) of timing performance (Chapter 1) suggests that timing performance in externally-initiated (EI) procedures conflates behavioral modes differentially sensitive to motivation, but that response-initiated (RI) procedures potentially dissociate these behavioral modes. That is, timing performance in RI procedures is expected to not conflate these behavioral modes. According to the discriminative RI hypothesis, as initiating-responses become progressively discriminable from target responses, initiating-responses increasingly dissociate interval timing and motivation. Rats were trained in timing procedures in which a switch from a Short to a Long interval indexes timing performance (a latency-to-switch, LTS), and were then challenged with pre-feeding and extinction probes. In experiments 1 (Chapter 2) and 2 (Chapter 3), discriminability of initiating-responses was varied as a function of time, location, and form for rats trained in a switch-timing procedure. In experiment 3 (Chapter 4), the generalizability of the discriminative RI hypothesis was evaluated in rats trained in a temporal bisection procedure. In experiment 3, but not 1 and 2, RI enhanced temporal control of LTSs relative to EI. In experiments 1 and 2, the robustness of LTS medians to pre-feeding but not extinction increased with the discriminability of initiating-responses from target responses. In experiment 3, the mean LTS was robust to pre-feeding in EI and RI. In all three experiments, pre-feeding increased LTS variability in EI and RI. These results provide moderate support for the discriminative RI hypothesis, indicating that initiating-responses selectively and partially dissociate interval timing and motivation processes. Implications for the study of cognition and motivation processes are discussed (Chapter 5).
ContributorsDaniels, Carter W (Author) / Sanabria, Federico (Thesis advisor) / McClure, Samuel M. (Committee member) / Wynne, Clive D.L. (Committee member) / Olive, Michael F. (Committee member) / Arizona State University (Publisher)
Created2018
Description
Previous research from Rajsic et al. (2015, 2017) suggests that a visual form of confirmation bias arises during visual search for simple stimuli, under certain conditions, wherein people are biased to seek stimuli matching an initial cue color even when this strategy is not optimal. Furthermore, recent research from our lab suggests that varying the prevalence of cue-colored targets does not attenuate the visual confirmation bias, although people still fail to detect rare targets regardless of whether they match the initial cue (Walenchok et al. under review). The present investigation examines the boundary conditions of the visual confirmation bias under conditions of equal, low, and high cued-target frequency. Across experiments, I found that: (1) People are strongly susceptible to the low-prevalence effect, often failing to detect rare targets regardless of whether they match the cue (Wolfe et al., 2005). (2) However, they are still biased to seek cue-colored stimuli, even when such targets are rare. (3) Regardless of target prevalence, people employ strategies when search is made sufficiently burdensome with distributed items and large search sets. These results further support previous findings that the low-prevalence effect arises from a failure to perceive rare items (Hout et al., 2015), while visual confirmation bias is a bias of attentional guidance (Rajsic et al., 2015, 2017).
ContributorsWalenchok, Stephen Charles (Author) / Goldinger, Stephen D (Thesis advisor) / Azuma, Tamiko (Committee member) / Homa, Donald (Committee member) / Hout, Michael C (Committee member) / McClure, Samuel M. (Committee member) / Arizona State University (Publisher)
Created2018
Description
The label-feedback hypothesis (Lupyan, 2007, 2012) proposes that language modulates low- and high-level visual processing, such as priming visual object perception. Lupyan and Swingley (2012) found that repeating target names facilitates visual search, reducing response times and increasing accuracy. Hebert, Goldinger, and Walenchok (under review) used a modified design to replicate and extend this finding, and concluded that speaking modulates visual search via template integrity. The current series of experiments 1) replicated the work of Hebert et al. with audio stimuli played through headphones instead of self-directed speech, 2) examined the label feedback effect under conditions of varying object clarity, and 3) explored whether the relative prevalence of a target’s audio label might modulate the label feedback effect (as in the low prevalence effect; Wolfe, Horowitz, & Kenner, 2005). Paradigms utilized both traditional spatial visual search and repeated serial visual presentation (RSVP). Results substantiated those found in previous studies—hearing target names improved performance, even (and sometimes especially) when conditions were difficult or noisy, and the relative prevalence of a target’s audio label strongly impacted its perception. The mechanisms of the label feedback effect––namely, priming and target template integrity––are explored.
ContributorsHebert, Katherine P (Author) / Goldinger, Stephen D (Thesis advisor) / Rogalsky, Corianne (Committee member) / McClure, Samuel M. (Committee member) / Benitez, Viridiana (Committee member) / Arizona State University (Publisher)
Created2019