Choice ball: a response interface for two-choice psychometric discrimination in head-fixed mice

Abstract

Sanders JI, Kepecs A. Choice ball: a response interface for twochoice psychometric discrimination in head-fixed mice. J Neurophysiol 108: 3416 -3423, 2012. First published September 26, 2012 doi:10.1152/jn.00669.2012The mouse is an important model system for investigating the neural circuits mediating behavior. Because of advances in imaging and optogenetic methods, head-fixed mouse preparations provide an unparalleled opportunity to observe and control neural circuits. To investigate how neural circuits produce behavior, these methods need to be paired with equally well-controlled and monitored behavioral paradigms. Here, we introduce the choice ball, a response device that enables two-alternative forcedchoice (2AFC) tasks in head-fixed mice based on the readout of lateral paw movements. We demonstrate the advantages of the choice ball by training mice in the random-click task, a two-choice auditory discrimination behavior. For each trial, mice listened to binaural streams of Poisson-distributed clicks and were required to roll the choice ball laterally toward the side with the greater click rate. In this assay, mice performed hundreds of trials per session with accuracy ranging from 95% for easy stimuli (large interaural click-rate contrast) to near chance level for low-contrast stimuli. We also show, using the record of individual paw strokes, that mice often reverse decisions they have already initiated and that decision reversals correlate with improved performance. The choice ball enables head-fixed 2AFC paradigms, facilitating the circuit-level analysis of sensory processing, decision making, and motor control in mice.

Signatures of a Statistical Computation in the Human Sense of Confidence

“…Therefore we used a perceptual decision task that provided precise experimental control over the discriminability of evidence sampled by our subjects on each trial, allowing us to compare the relationships among observable variables to the predictions shown in Figure 1. We designed a two-alternative forced choice perceptual decision task in which we varied auditory sensory evidence in a graded manner (Brunton et al, 2013; Sanders and Kepecs, 2012). Subjects listened to separate Poisson click streams delivered independently to each ear, and indicated the faster clicking stream within 3 seconds with a button press (Figure 2A).…”

The Limits of Deliberation in a Perceptual Decision Task

“…Brunton 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).…”

Probing perceptual decisions in rodents

“…A further refinement of the experimental design, used in a few rodent studies 31, 40, 72–74 involves presenting not one but two stimuli (simultaneously or in succession) and asking the subject which of the two has the attribute in question. This design is called “forced choice” or (since the choice is between two stimuli), “two-alternative forced choice”.…”

“…Other methods distinguish the actions that report a percept from those that obtain the rewards. For instance, mice can use their paws to operate one of two levers or a trackball 72 in one of two directions (Fig. 2 b ).…”