Further experiments will be needed to test this hypothesis. Under this interpretation, the present results are likely to reflect features of the task rather than the modality or species. This has several implications. First, rodents performing tasks that are dominated by uncorrelated sensory noise may indeed show the expected benefits of extended temporal integration (B.W. Brunton RG7204 supplier and C. Brody, 2009, Soc. Neurosci., abstract; P. Reinagel et al., 2012; Sanders

and Kepecs, 2012). Second, decisions that favor short sampling time are likely not to be limited to rodents or olfaction ( Uchida et al., 2006; Kahneman, 2011; Stanford et al., 2010). Indeed, it has long been appreciated that performance on psychophysical tasks may saturate with as little as 100–200 ms of stimulus exposure ( Barlow, 1958; Watson, 1979). For example, in random dot motion discrimination by humans, if difficulty is manipulated by lowering coherence, accuracy increases up to 3 s of stimulus exposure, but if it is manipulated by lowering contrast, only up to 0.3 s ( Burr and Santoro, 2001). Finally, the present results are likely not applicable to all olfactory decisions

but specific to olfactory categorization SAHA HDAC decisions. Different tasks such as odor detection, odor mixture segmentation or odor source tracking will each make different demands, tapping

into different underlying neural mechanisms to overcome different sources of uncertainty. Thirty-seven male Long-Evans rats (250 g at the start of training) were trained and tested using procedures approved by the Cold Spring Harbor Laboratory, whatever Institutional Animal Care and Use Committee. Rats were trained and tested on a two-alternative choice odor mixture categorization task where water was used as a reward as described previously (Uchida and Mainen, 2003). The animals were pair-housed (except where noted) and maintained on a reverse 12 hr light/dark cycle and tested during their dark period. Each rat performed one session of 45–60 min per day (250–400 trials), 5 days per week for a period of 8–20 weeks. Rats were allowed free access to food but were restricted to water available during the behavioral session and for 30 min after the session and during non training days; water amounts were adjusted to ensure animals maintained no less than 85% of ad libitum weight at any time. A different set of naive rats were used for each experimental condition unless otherwise noted. The behavioral setup consisted of a box of 20 × 20 cm with a panel containing three conical ports (2.5 cm diameter, 1 cm depth) (Uchida and Mainen, 2003).