Demonstration of nondeclarative sequence learning in mice: Development of an animal analog of the human serial reaction time task: Figure 1.

Abstract

In this paper, we demonstrate nondeclarative sequence learning in mice using an animal analog of the human serial reaction time task (SRT) that uses a within-group comparison of behavior in response to a repeating sequence versus a random sequence. Ten female B6CBA mice performed eleven 96-trial sessions containing 24 repetitions of a 4-trial sequence. During the 12th session, the repeating sequence was replaced with the random sequence halfway through the session. Reaction time (RT) to respond to an illuminated nose-poke was recorded, and performance was compared at the halfway point in each session to test for any change in behavior. For learning effect, RTs decreased over the no-switch repeating-sequence sessions. For interference effect, behavior did not change appreciably at the halfway point during the last repeating-sequence session. However, RTs deteriorated significantly after the switch from repeating to random sequences halfway through session 12. The mice demonstrated a robust interference effect when switched from repeating to random sequences. This pattern of behavior in humans performing the SRT is interpreted as evidence of nondeclarative sequence learning. The similarity between the human and mouse SRTs will enable more direct comparisons of mouse-human nondeclarative memory behavior and will provide a useful behavioral end-point in mouse-models of basal ganglia dysfunction.In humans, the serial reaction time task (SRT) is a nondeclarative/ implicit memory task that produces sequence learning through repetition of uncued and unannounced serially ordered stimuli. Learning is assessed by observing a deterioration in task performance when a random sequence replaces a regularly repeating sequence (the "interference effect"). Subjects with basal ganglia disorders such as Huntington's disease (Knopman and Nissen 1991; Willingham and Koroshetz 1993), Parkinson's disease (Ferraro et al. 1993;Pascual-Leone et al. 1993;Jackson et al. 1995;Westwater et al. 1998;Sommer et al. 1999;Stefanova et al. 2000) or pharmacologic treatments that affect the basal ganglia (Knopman 1991) demonstrate greatly reduced, or entirely absent, interference effects, indicating compromised implicit learning. These SRT deficits in subjects with basal ganglia dysfunction are not simply due to motor performance dysfunction (Harrington et al. 1990), as subjects with damage restricted to the basal ganglia as a consequence of infarct or hemorrhage are significantly impaired in both a motor and nonmotor version of the SRT (Vakil et al. 2000). Furthermore, Vakil et al. (2000) found that while the basal-ganglia infarct subjects were significantly impaired in the SRT in comparison with intact-control subjects, the two groups did not differ on several tests of declarative (explicit) memory function.In recent years, there has been an ever growing list of genetic mouse models of basal ganglia function and disorders. These include many knockout mice probing receptor and transporter function (Centonze et al. 2003;Metzger et al. 2002;Viggiano e...

Implicit learning in cotton-top tamarins (Saguinus oedipus) and pigeons (Columba livia)

“…These findings join a number of other demonstrations using the SRT procedure with nonhumans in which evidence has emerged of decreases in latencies during pattern training and increases during a random test (in rats: Christie & DalrympleAlford, 2004;Domenger & Schwarting, 2005; in mice: Christie & Hersch, 2004;in rhesus macaques: Procyk, Dominey, Amiez, & Joseph, 2000;in pigeons: Froehlich, Herbranson, Loper, Wood, & Shimp, 2004, Herbranson & Shimp, 2008Herbranson & Stanton, 2011;in Bengalese finches: Yamazaki, Suzuki, Inada, Iriki, & Okanoya, 2012). These studies have demonstrated that some learning occurs in nonhumans when reinforcement is randomly presented.…”

Unaltered Instrumental Learning and Attenuated Body-Weight Gain in Rats During Non-rotating Simulated Shiftwork

“…The performance of more complex cognitive tasks (e.g., Christie & Hersch, 2004;Leenaars et al, 2012;McCoy et al, 2007) may be more sensitive to disturbance by prolonged (shift)work. When mainly interested in the effect of motivation on task performance, a different type of task could be preferable, for example, a task implementing ratio lever pressing or imposing delays.…”

Oculomotor and manual indexes of incidental and intentional spatial sequence learning during middle childhood and adolescence

“…Studies that included children younger than age 12 years of age yielded inconsistent results, with some Wndings suggesting that sequence learning continues to develop until age 12. However, it is important to keep in mind that even pigeons, rats, and mice show evidence of sequence learning (Bailey & Mair, 2006;Christie & Dalrymple-Alford, 2004;Christie & Hersch, 2004;Froelich, Herbranson, Loper, Wood, & Shimp, 2004). Thus, before concluding that spatial sequence learning is a higher cognitive skill requiring cortical maturation, it is crucial to conduct developmental studies spanning the period from infancy to 12 years of age to address methodological questions and to obtain a better understanding of the development of diVerent aspects of spatial sequence learning.…”