Motion perception in the common marmoset

Abstract

words)Visual motion processing is a well-established model system for studying neural population codes in primates. The common marmoset, a small new world primate, offers unparalleled opportunities to probe these population codes in key motion processing areas, such as cortical areas MT and MST, because these areas are accessible for imaging and recording at the cortical surface. However, little is currently known about the perceptual abilities of the marmoset. Here, we introduce a paradigm for studying motion perception in the marmoset and compare their psychophysical performance to human observers. We trained two marmosets to perform a motion estimation task in which they provided an analog report of their perceived direction of motion with an eye movement to a ring that surrounded the motion stimulus. Marmosets and humans exhibited similar trade-offs in speed vs. accuracy: errors were larger and reaction times were longer as the strength of the motion signal was reduced. Reverse correlation on the temporal fluctuations in motion direction revealed that both species exhibited short integration windows, however, marmosets had substantially less non-decision time than humans. Our results provide the first quantification of motion perception in the marmoset and demonstrate several advantages to using analog estimation tasks.

Lapses in perceptual decisions reflect exploration

“…Uncertainty-guided exploration also predicts that exploratory choices, and consequently lapses, should decrease with training as the animal becomes more certain of the rules and expected rewards, explaining training-dependent effects on lapses in our rats ( Figure 3—figure supplement 2g, right) and similar effects reported in primates ( Law and Gold, 2009 ; Cloherty et al, 2019 ). This can also potentially explain why children have higher lapse rates ( Witton et al, 2017 ; Manning et al, 2018 ), as they have been shown to be more exploratory in their decisions than adults ( Lucas et al, 2014 ).…”

“…right) and similar effects reported in primates (Law and Gold, 2009;Cloherty et al, 2019). This can also potentially explain why children have higher lapse rates (Witton, Talcott, and Henning, 2017;Manning et al, 2018), as they have been shown to be more exploratory in their decisions than adults (Lucas et al, 2014).…”

“…A number of recent observations have cast doubt on fixed early- or late-stage noise as satisfactory explanations for lapses. For instance, many of these explanations predict that lapses should occur at a constant rate, while in reality, lapses are known to reduce in frequency with learning in nonhuman primates ( Law and Gold, 2009 ; Cloherty et al, 2019 ). Further, they can occur with different frequencies for different stimuli even within the same subject (in rodents, Nikbakht et al, 2018 ; and humans, Mihali et al, 2018 ; Bertolini et al, 2015 ; Flesch et al, 2018 ), suggesting that they may reflect task-specific, associative processes that can vary within a subject.…”

Marmosets: a promising model for probing the neural mechanisms underlying complex visual networks such as the frontal–parietal network

“…Recent research has also confirmed that marmosets can be trained to perform a wide range of visual, oculomotor and cognitive tasks while head restrained, in a manner comparable to macaques and humans (Mitchell et al 2014Johnston et al 2019;Cloherty et al 2020). The marmoset brain also has major advantages over rodents and other primate models for neurophysiological research.…”

A value-based explanation for lapses in perceptual decisions

“…The last key prediction of the ideal observer model is that performance should asymptote at 0 and 1 for very easy stimuli. However, in practice this is often not the case, as has been observed in a large number of psychophysical studies in humans (Treutwein and Strasburger, 1999;Klein, 2001;Wichmann and Hill, 2001;Flesch et al, 2018;Mihali et al, 2018), nonhuman primates (Law and Gold, 2009;Cohen and Maunsell, 2009;Cloherty et al, 2019), mice (Busse et al, 2011;Burgess et al, 2017;Odoemene et al, 2018;Pinto et al, 2018;Wang et al, 2018;Lak et al, 2018) and rats (Raposo et al, 2012;Brunton, Botvinick, and Brody, 2013;Scott et al, 2015;Nikbakht et al, 2018;Piet et al, 2017;Mendonca et al, 2018). These deviations in the asymptotes are known as lapses, since they are assumed to arise from occasional lapses in attention, or errors in motor execution (Wichmann and Hill, 2001).…”