Scheduled daily mating induces circadian anticipatory activity rhythms in the male rat

Daily schedules of limited access to food, palatable high calorie snacks, water and salt can induce circadian rhythms of anticipatory locomotor activity in rats and mice. All of these stimuli are rewarding, but whether anticipation can be induced by neural correlates of reward independent of metabolic perturbations associated with manipulations of food and hydration is unclear. Three experiments were conducted to determine whether mating, a non-ingestive behavior that is potently rewarding, can induce circadian anticipatory activity rhythms in male rats provided scheduled daily access to steroid-primed estrous female rats. In Experiment 1, rats anticipated access to estrous females in the mid-light period, but also exhibited post-coital eating and running. In Experiment 2, post-coital eating and running were prevented and only a minority of rats exhibited anticipation. Rats allowed to see and smell estrous females showed no anticipation. In both experiments, all rats exhibited sustained behavioral arousal and multiple mounts and intromissions during every session, but ejaculated only every 2-3 days. In Experiment 3, the rats were given more time with individual females, late at night for 28 days, and then in the midday for 28 days. Ejaculation rates increased and anticipation was robust to night sessions and significant although weaker to day sessions. The anticipation rhythm persisted during 3 days of constant dark without mating. During anticipation of nocturnal mating, the rats exhibited a significant preference for a tube to the mating cage over a tube to a locked cage with mating cage litter. This apparent place preference was absent during anticipation of midday mating, which may reflect a daily rhythm of sexual reward. The results establish mating as a reward stimulus capable of inducing circadian rhythms of anticipatory behavior in the male rat, and reveal a critical role for ejaculation, a modulatory role for time of day, and a potential confound role for uncontrolled food intake.     

Top-down anticipatory control in prefrontal cortex

Summary The prefrontal cortex has been implicated in a wide variety of executive functions, many involving some form of anticipatory attention. Anticipatory attention involves the pre-selection of specific sensory circuits to allow fast and efficient stimulus processing and a subsequently fast and accurate response. It is generally agreed that the prefrontal cortex plays a critical role in anticipatory attention by exerting a facilitatory “top-down” bias on sensory pathways. In this paper we review recent results indicating that synchronized activity in prefrontal cortex, during anticipation of visual stimulus, can predict features of early visual stimulus processing and behavioral response. Although the mechanisms involved in anticipatory attention are still largely unknown, we argue that the synchronized oscillation in prefrontal cortex is a plausible candidate during sustained visual anticipation. We further propose a learning hypothesis that explains how this top-down anticipatory control in prefrontal cortex is learned based on accumulated prior experience by adopting a Temporal Difference learning algorithm.     

Attenuation of the neuronal stress responsiveness and corticotrophin releasing hormone synthesis after sexual activity in male rats

Beneficial effects of sexual activity and mating on the responsiveness to environmental stress can be observed in humans and other mammalian species alike, but the underlying neurobiological mechanisms are largely unknown. Sexual activity and mating with a receptive female has recently been shown to reduce the subsequent emotional stress response via activation of the brain oxytocin system. Therefore, we investigated the neuronal and hormonal responses to an acute stressor (forced swimming) after mating in male rats.Attenuation of the stress-induced increase of c-fos and CRH mRNA expression within the hypothalamic paraventricular nucleus 4 h after mating revealed that sexual activity reduced neuronal reactivity in this region. However, this effect was independent of oxytocin as oxytocin receptor blockade, by central administration of an oxytocin receptor antagonist, after mating did not prevent the reduced expression of c-fos mRNA in response to stressor exposure. Mating itself stimulated corticotrophin (ACTH) and corticosterone secretion, which was absent in males after contact with an unreceptive female (non-mated group). However, ACTH and corticosterone responses to forced swimming applied either 45 min or 4 h after female contact were similar between mated and non-mated males. These findings provide evidence for a stress-protective effect of sexual activity and mating in male rats and for dissociation between neuronal and neuroendocrine stress responses.     

Anticipatory activity rhythms under daily schedules of water access in the rat.

Rats anticipate a fixed daily feeding time by entrainment of a component of their multioscillatory circadian system. The range of stimuli capable of entraining this component is little studied. Previous studies suggest that restricted water access is not an effective entrainment stimulus, as measured by general locomotion. The present study re-examined the issue, using two other measures of activity: wheel running and activity at a food-water delivery bin. Rats restricted to 1 hr of water each day in the middle of the light and to food in the 12-hr dark period showed no anticipation of this event in the wheel-running measure, but some rats did show anticipation in the delivery bin activity measure. Rats (bin activity measure only) restricted to 1 hr of water and 1 hr of food separated by intervals of 7, 10, or 12 hr, in either the light or the dark, showed consistent anticipation of food access time but little or no anticipation of water access time. Water access time also did not sustain food anticipatory rhythms in animals whose food-water schedules were reversed. However, deprivation of water or of both food and water for 72 or 90 hr was usually associated with specific increases in bin activity at both the usual feeding and drinking times. Water access, like food, appears to provide cues capable of entraining an anticipatory circadian mechanism. Differences in the type and amount of anticipatory activity preceding these events may reflect differences in the strengths of the two entrainment cues and/or in the activity levels or specific behavioral strategies promoted by hunger and thirst.     

Administration of an oxytocin receptor antagonist attenuates sexual motivation in male rats

In male rats, oxytocin impacts both sexual arousal and certain types of consummatory sexual behaviors. However, the role of oxytocin in the motivational aspects of sexual behavior has received limited attention. Given the role that oxytocin signaling plays in consummatory sexual behaviors, it was hypothesized that pharmacological attenuation of oxytocin signaling would reduce sexual motivation in male rats. Sexually experienced Long-Evans male rats were administered either an oxytocin receptor antagonist (L368,899 hydrochloride; 1 mg/kg) or vehicle control into the intraperitoneal cavity 40 min prior to placement into the center chamber of a three-chambered arena designed to assess sexual motivation. During the 20-minute test, a sexually experienced stimulus male rat and a sexually receptive stimulus female rat were separately confined to smaller chambers that were attached to the larger end chambers of the arena. However, physical contact between test and stimulus rats was prevented by perforated dividers. Immediately following the sexual motivation test, test male rats were placed with a sexually receptive female to examine consummatory sexual behaviors. Although both drug and vehicle treated rats exhibited a preference for the female, treatment with an oxytocin receptor antagonist decreased the amount of time spent with the female. There were no differences between drug and vehicle treated rats in either general activity, exploratory behaviors, the amount of time spent near the stimulus male rat, or consummatory sexual behaviors. Extending previous findings, these results indicate that oxytocin receptors are involved in sexual motivation in male rats.     

Stereotypic route-tracing in experimentally caged songbirds correlates with general behavioural disinhibition

Repetitive, unvarying and apparently functionless behaviours called stereotypies are common in caged animals, but the mechanisms of cage stereotypy have remained elusive. We found that stereotypies correlate with a sign of altered brain functioning, the general disinhibition of behaviour, found in stereotyping human patients and animals treated with psychostimulants. We investigated route-tracing stereotypy in blue tits, Parus caeruleus, and marsh tits,P. palustris , caged in a behavioural research laboratory. In experiment 1, stereotypy correlated with disinhibition of responses, shown as persistent responding in extinction learning. In experiment 2a, stereotypy in blue tits correlated with repetitive sequence generation on a ‘gambling task’ that specifically measures disinhibited striatal functioning in humans and correlates with stereotypy in autistic and schizophrenic patients. In experiment 2b, the behavioural disinhibition correlated with stereotypy also affected food-storing behaviour in marsh tits, in particular their response to cache pilfering. In experiment 3, the sequencing of nonstereotypic home cage behaviour was correlated with stereotypy. Finally, changes in stereotypy induced by environmental enrichment correlated with changes in these measures of altered behavioural control. These results suggest that housing conditions that cause stereotypy thus alter many aspects of the behavioural control of caged subjects, mediated by altered striatal functioning. The implications for understanding cage stereotypies in laboratory, farm and zoo animals, and for laboratory-based behavioural experiments, are discussed. We suggest that improving housing conditions so that cage stereotypies do not develop would enhance the validity of laboratory-based behavioural research.     

Use of a conditioning technique to reduce stress associated with repeated intra-peritoneal injections in laboratory rats

We hypothesized that using classical conditioning to pair a stressful procedure such as injection with a rewarding experience decreases the stress associated with repeated exposure to this procedure. We investigated the effectiveness of pairing repeated intra-peritoneal injections with a positive stimulus to reduce physiological and behavioural stress responses of laboratory rats by comparing injection with 1 ml/kg of saline followed by one of three different reward types (food treat (F), stroking (S) and tickling (T)), delivered in a treatment box, with two control conditions (handling without injection (CH) and injected (CI)) followed by an equivalent period in the treatment box. Treatments were applied to rats (N = 40; 8 rats/treatment) daily for 10 days. Audible and 50 kHz (laughing) vocalizations were assessed during handling and while in the treatment box. Chromodacryorrhea (an indicator of stress) was assessed daily in the home cage. Body weight, and behaviour in the Human Approach (HA) test, were assessed before (baseline) and after the 10-day treatment period. Behaviour in the Elevated Plus Maze (EPM) test was assessed after the 10-day treatment period. Rats on all treatments produced more chromodacryorrhea during the treatment period compared to baseline, suggesting that all treatments induced stress. Principal component analyses on behaviour in the HA and EPM tests revealed two and three factors that explained 86.8% and 98.7% of total variance, respectively. Multivariate analysis of variance on these factors, along with the other variables, revealed a significant contrast between CH and the other treatments. CH rats performed fewer audible vocalizations when handled compared to rats given injections. We found no clear benefit of providing a food treat, stroking, or tickling to alleviate stress associated with injection under the conditions of this study, possibly due to differences between rats in their perception of the aversiveness of handling restraint and injection, their stress response style (active or passive), and their perception of the pleasantness of the different rewards. Rats on all treatments emitted 50 kHz chirps in the treatment box, suggesting that being placed in the box after handling was rewarding regardless of treatment.     

Dopaminergic Regulation of Circadian Food Anticipatory Activity Rhythms in the Rat

Circadian activity rhythms are jointly controlled by a master pacemaker in the hypothalamic suprachiasmatic nuclei (SCN) and by food-entrainable circadian oscillators (FEOs) located elsewhere. The SCN mediates synchrony to daily light-dark cycles, whereas FEOs generate activity rhythms synchronized with regular daily mealtimes. The location of FEOs generating food anticipation rhythms, and the pathways that entrain these FEOs, remain to be clarified. To gain insight into entrainment pathways, we developed a protocol for measuring phase shifts of anticipatory activity rhythms in response to pharmacological probes. We used this protocol to examine a role for dopamine signaling in the timing of circadian food anticipation. To generate a stable food anticipation rhythm, rats were fed 3h/day beginning 6-h after lights-on or in constant light for at least 3 weeks. Rats then received the D2 agonist quinpirole (1 mg/kg IP) alone or after pretreatment with the dopamine synthesis inhibitor α-methylparatyrosine (AMPT). By comparison with vehicle injections, quinpirole administered 1-h before lights-off (19h before mealtime) induced a phase delay of activity onset prior to the next meal. Delay shifts were larger in rats pretreated with AMPT, and smaller following quinpirole administered 4-h after lights-on. A significant shift was not observed in response to the D1 agonist SKF81297. These results provide evidence that signaling at D2 receptors is involved in phase control of FEOs responsible for circadian food anticipatory rhythms in rats.     

Response to novel object in Wistar and wild-type (WWCPS) rats

Laboratory rats react to a novel object with a rapid redirection of exploratory behaviour towards the source of the novelty and a subsequent decline of this neotic preference with repeated object exposure. Studies with wild Rattus norvegicus have shown that a novel object in a familiar cage results in avoidance reactions (neophobia) in those animals, but it is also well established that the wild R. norvegicus show strong aversive reactivity to a variety of high intensity stimuli. In this study we aimed to create low-stress conditions enabling the comparison of spontaneous exploratory behaviour directed at a novel object in male (age = 80 days) “wild-type” WWCPS rats (n = 21; fourth generation bred in captivity) and Wistar (n = 24) rats. The study involved repeated placing of individual animals in the experimental chamber for 15 (6 min) trials on consecutive days. On the 11th day the novel object was introduced. Animals were tested in darkness and without human presence. Under these conditions neither WWCPS nor Wistar have shown behavioural signs of high emotional arousal, both lines have shown comparable general levels of experimental cage exploration and the positive new object exploratory reaction was observed only in Wistar rats.     

Distinguishing between anticipatory and responsive plasticity in a seasonally polyphenic butterfly

Seasonal generations of short-lived organisms often differ in their morphological, behavioural and life history traits, including body size. These differences may be either due to immediate effects of seasonally variable environment on organisms (responsive plasticity) or rely on presumably adaptive responses of organisms to cues signalizing forthcoming seasonal changes (anticipatory plasticity). When directly developing individuals of insects are larger than their overwintering conspecifics, the between-generation differences are typically ascribed to responsive plasticity in larval growth. We tested this hypothesis using the papilionid butterly Iphiclides podalirius as a model species. In laboratory experiments, we demonstrated that seasonal differences in food quality could not explain the observed size difference. Similarly, the size differences are not likely to be explained by the immediate effects of ambient temperature and photoperiod on larval growth. The qualitative pattern of natural size differences between the directly developing and diapausing butterflies could be reproduced in the laboratory as a response to photoperiod, indicating anticipatory character of the response. Directly developing and diapausing individuals followed an identical growth trajectory until the end of the last larval instar, with size differences appearing just a few days before pupation. Taken together, various lines of evidence suggest that between-generation size differences in I. podalirius are not caused by immediate effects of environmental factors on larval growth. Instead, these differences rather represent anticipatory plasticity and are thus likely to have an adaptive explanation. It remains currently unclear, whether the seasonal differences in adult size per se are adaptive, or if they constitute co-product of processes related to the diapause. Our study shows that it may be feasible to distinguish between different types of plasticity on the basis of empirical data even if fitness cannot be directly measured, and contributes to the emerging view about the predominantly adaptive nature of seasonal polyphenisms in insects.     

Children and Older Adults Exhibit Distinct Sub-Optimal Cost-Benefit Functions when Preparing to Move Their Eyes and Hands

Numerous activities require an individual to respond quickly to the correct stimulus. The provision of advance information allows response priming but heightened responses can cause errors (responding too early or reacting to the wrong stimulus). Thus, a balance is required between the online cognitive mechanisms (inhibitory and anticipatory) used to prepare and execute a motor response at the appropriate time. We investigated the use of advance information in 71 participants across four different age groups: (i) children, (ii) young adults, (iii) middle-aged adults, and (iv) older adults. We implemented ‘cued’ and ‘non-cued’ conditions to assess age-related changes in saccadic and touch responses to targets in three movement conditions: (a) Eyes only; (b) Hands only; (c) Eyes and Hand. Children made less saccade errors compared to young adults, but they also exhibited longer response times in cued versus non-cued conditions. In contrast, older adults showed faster responses in cued conditions but exhibited more errors. The results indicate that young adults (18–25 years) achieve an optimal balance between anticipation and execution. In contrast, children show benefits (few errors) and costs (slow responses) of good inhibition when preparing a motor response based on advance information; whilst older adults show the benefits and costs associated with a prospective response strategy (i.e., good anticipation).     

The effect of environmental enrichment on the behaviour of caged rabbits (Oryctolagus cuniculus)

Behaviour and use of the cage area were studied in 96 rabbits (Oryctolagus cuniculus) kept in an enriched cage system - with access to shelter and raised height at the back of the cage - and in a conventional cage system to estimate the effects of the environmental enrichment on the rabbits' welfare. The rabbits' behaviour and placement in the cage were observed, using continuous video recording through 24 h and direct scan sampling during the daytime. In addition, an open-field test was carried out with each rabbit, and after every single test, the rabbits' timidity of being captured was recorded. Rabbits kept in the conventional cage system, especially the females, showed more restlessness, excessive grooming, bar-gnawing and timidity than rabbits kept in the enriched cage system. This indicates increased stress in the rabbits kept in the conventional cage system. All the rabbits performed most of the active behavioural elements in the daytime and were resting mostly at night that shows that the rabbits in both cage systems were adapted to the daily activity in the animal unit; the enrichment had no effect on the daytime activity.Only a few rabbits, particularly the females, used the box as a shelter or resting-place. On the other hand, they more often used the roof of the box as a look-out or resting-place. Furthermore, the rabbits' behaviour showed that they utilised the raised height in the enriched cage system.These results indicate that rabbits kept in an enriched cage system, particularly the females, had better welfare than rabbits kept in a conventional cage system because they had access to shelter and a better chance of interacting with the environment.     

Embryonic temperature shapes behavioural change following social experience in male leopard geckos, Eublepharis macularius

Individual variation in behavioural expression and behavioural plasticity exist in all species, and early experiences are critical determinants of both. The leopard gecko is a lizard with temperature-dependent sex determination, and in this species, embryonic incubation temperature (IncT) affects the display of social behaviours. For example, adult males hatched from eggs incubated at an IncT that produces predominantly males (male-biased IncT, 32.5°C) are more aggressive and less sexually active than males hatched from eggs at an IncT that produces predominantly females (female-biased IncT, 30°C). It is not known, however, whether IncT influences behavioural plasticity in adulthood. We assessed whether adult males hatched from eggs incubated at female- and male-biased IncTs showed different changes in territorial behaviour (scent marking in an empty test arena), anticipatory behaviours (activity, scent marking and tail vibrations in response to cues that predict the introduction of a female) and courtship behaviour following social interactions with females. We found that heterosexual social experiences increased territorial behaviour and the display of anticipatory behaviours in males from the female-biased IncT but not in males from the male-biased IncT. This difference was not due to differences in the amount of social experiences acquired, and the greater change in anticipatory behaviour in males from the female-biased IncT suggest that they acquired sexual conditioning more readily. Differences in sex steroid concentrations or neural metabolism caused by IncT could underlie this difference. These results highlight the profound implications of maternal nest site selection for offspring phenotype and plasticity in this species.Copyright 2003 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.      

Daily timed sexual interaction induces moderate anticipatory activity in mice

Anticipation of resource availability is a vital skill yet it is poorly understood in terms of neuronal circuitry. Rodents display robust anticipatory activity in the several hours preceding timed daily access to food when access is limited to a short temporal duration. We tested whether this anticipatory behavior could be generalized to timed daily social interaction by examining if singly housed male mice could anticipate either a daily novel female or a familiar female. We observed that anticipatory activity was moderate under both conditions, although both a novel female partner and sexual experience are moderate contributing factors to increasing anticipatory activity. In contrast, restricted access to running wheels did not produce any anticipatory activity, suggesting that an increase in activity during the scheduled access time was not sufficient to induce anticipation. To tease apart social versus sexual interaction, we tested the effect of exposing singly housed female mice to a familiar companion female mouse daily. The female mice did not show anticipatory activity for restricted female access, despite a large amount of social interaction, suggesting that daily timed social interaction between mice of the same gender is insufficient to induce anticipatory activity. Our study demonstrates that male mice will show anticipatory activity, albeit inconsistently, for a daily timed sexual encounter.     

Pavlovian Conditioned Approach Training in Rats

Cues that are contingently paired with unconditioned, rewarding stimuli can acquire rewarding properties themselves through a process known as the attribution of incentive salience, or the transformation of neutral stimuli into attractive, "wanted'' stimuli capable of motivating behavior. Pavlovian conditioned approach (PCA) develops after the response-independent presentation of a conditioned stimulus (CS; e.g., a lever) that predicts the delivery of an unconditioned stimulus (US; e.g., a food pellet) and can be used to measure incentive salience. During training, three patterns of conditioned responses (CRs) can develop: sign-tracking behavior (CS-directed CR), goal-tracking behavior (US-directed CR), and an intermediate response (both CRs). Sign-trackers attribute incentive salience to reward-related cues and are more vulnerable to cue-induced reinstatement of drug-seeking as well as other addiction-related behaviors, making PCA a potentially valuable procedure for studying addiction vulnerability. Here, we describe materials and methods used to elicit PCA behavior from rats as well as analyze and interpret PCA behavior in individual experiments.     

Alterations in plasma concentrations of testosterone, LH, and prolactin associated with mating in the male rat.

The hormonal response of the male rat to sexual activity was investigated in two studies. In the first, no evidence of a chronic elevation in plasma levels of testosterone (T), LH, or prolactin (PRL) was observed in sexually experienced rats compared to naive controls. Both groups showed an acute increase in plasma levels of all three hormones following mating, but the increases shown by the experienced group were more pronounced. In the second study, plasma levels of T, LH and PRL rose in sexually experienced male rats following exposure to a mating arena whether it contained an estrous female, an anestrous female, or no other animal. However, the increases were considerably larger in the group exposed to estrous females. It is suggested that plasma hormones rise in anticipation of mating, although not to the same extent as following mating, and that the anticipatory rise may function to initiate or facilitate mating behavior.     

Placenta on pups' skin accelerates onset of maternal behaviour in non-pregnant rats

Previous research has indicated that virgin rats (Rattus norvegicus) behave maternally (sensitize) more rapidly if kept in close proximity with pups. Since both parturient rats and a large percentage of virgin rats avidly consume placenta, we tested whether placenta and amnionic fluid, applied to the skin of the stimulus pups, would draw the female adults into closer contact with the pups and therefore hasten the onset of maternal behaviour. The results indicated that the procedure indeed shortened the maternal sensitization latency. Furthermore, this effect was not due to the wetness of the pups, to the presence of placenta in the cage, or to the the adults having previously ingested placenta. Other attractive ingestibles applied to the pups' skin produced an intermediate, but not significant, shortening of the maternal sensitization latency.     

Palatable Meal Anticipation in Mice

The ability to sense time and anticipate events is a critical skill in nature. Most efforts to understand the neural and molecular mechanisms of anticipatory behavior in rodents rely on daily restricted food access, which induces a robust increase of locomotor activity in anticipation of daily meal time. Interestingly, rats also show increased activity in anticipation of a daily palatable meal even when they have an ample food supply, suggesting a role for brain reward systems in anticipatory behavior, and providing an alternate model by which to study the neurobiology of anticipation in species, such as mice, that are less well adapted to “stuff and starve” feeding schedules. To extend this model to mice, and exploit molecular genetic resources available for that species, we tested the ability of wild-type mice to anticipate a daily palatable meal. We observed that mice with free access to regular chow and limited access to highly palatable snacks of chocolate or “Fruit Crunchies” avidly consumed the snack but did not show anticipatory locomotor activity as measured by running wheels or video-based behavioral analysis. However, male mice receiving a snack of high fat chow did show increased food bin entry prior to access time and a modest increase in activity in the two hours preceding the scheduled meal. Interestingly, female mice did not show anticipation of a daily high fat meal but did show increased activity at scheduled mealtime when that meal was withdrawn. These results indicate that anticipation of a scheduled food reward in mice is behavior, diet, and gender specific.     

Alcohol-Preferring Rats Show Goal Oriented Behaviour to Food Incentives but Are Neither Sign-Trackers Nor Impulsive

Drug addiction is often associated with impulsivity and altered behavioural responses to both primary and conditioned rewards. Here we investigated whether selectively bred alcohol-preferring (P) and alcohol-nonpreferring (NP) rats show differential levels of impulsivity and conditioned behavioural responses to food incentives. P and NP rats were assessed for impulsivity in the 5-choice serial reaction time task (5-CSRTT), a widely used translational task in humans and other animals, as well as Pavlovian conditioned approach to measure sign- and goal-tracking behaviour. Drug-naïve P and NP rats showed similar levels of impulsivity on the 5-CSRTT, assessed by the number of premature, anticipatory responses, even when the waiting interval to respond was increased. However, unlike NP rats, P rats were faster to enter the food magazine and spent more time in this area. In addition, P rats showed higher levels of goal-tracking responses than NP rats, as measured by the number of magazine nose-pokes during the presentation of a food conditioned stimulus. By contrast, NP showed higher levels of sign-tracking behaviour than P rats. Following a 4-week exposure to intermittent alcohol we confirmed that P rats had a marked preference for, and consumed more alcohol than, NP rats, but were not more impulsive when re-tested in the 5-CSRTT. These findings indicate that high alcohol preferring and drinking P rats are neither intrinsically impulsive nor do they exhibit impulsivity after exposure to alcohol. However, P rats do show increased goal-directed behaviour to food incentives and this may be associated with their strong preference for alcohol.     

Oscillatory Activity in the Medial Prefrontal Cortex and Nucleus Accumbens Correlates with Impulsivity and Reward Outcome

Actions expressed prematurely without regard for their consequences are considered impulsive. Such behaviour is governed by a network of brain regions including the prefrontal cortex (PFC) and nucleus accumbens (NAcb) and is prevalent in disorders including attention deficit hyperactivity disorder (ADHD) and drug addiction. However, little is known of the relationship between neural activity in these regions and specific forms of impulsive behaviour. In the present study we investigated local field potential (LFP) oscillations in distinct sub-regions of the PFC and NAcb on a 5-choice serial reaction time task (5-CSRTT), which measures sustained, spatially-divided visual attention and action restraint. The main findings show that power in gamma frequency (50–60 Hz) LFP oscillations transiently increases in the PFC and NAcb during both the anticipation of a cue signalling the spatial location of a nose-poke response and again following correct responses. Gamma oscillations were coupled to low-frequency delta oscillations in both regions; this coupling strengthened specifically when an error response was made. Theta (7–9 Hz) LFP power in the PFC and NAcb increased during the waiting period and was also related to response outcome. Additionally, both gamma and theta power were significantly affected by upcoming premature responses as rats waited for the visual cue to respond. In a subgroup of rats showing persistently high levels of impulsivity we found that impulsivity was associated with increased error signals following a nose-poke response, as well as reduced signals of previous trial outcome during the waiting period. Collectively, these in-vivo neurophysiological findings further implicate the PFC and NAcb in anticipatory impulsive responses and provide evidence that abnormalities in the encoding of rewarding outcomes may underlie trait-like impulsive behaviour.