Behavioral neuroscience最新文献

N-methyl-D-aspartate (NMDA) receptor antagonists are increasingly used for treating mood disorders, but there is much to learn about their cognitive effects. Research shows NMDA receptor antagonists have varying effects in temporal decision making, either increasing or decreasing optimal choice behaviors related to impulsiveness and delay sensitivity. To clarify their role in these behaviors, we investigated the role of the NMDA receptor antagonist MK-801 in the diminishing returns designed to investigate the ability to delay immediate rewards to optimize total rewards per session. Male and female rats were given the option to choose either a fixed delay lever that returned reward after 10 s or a progressive delay lever that delivered reward with no initial delay but increased by 1 s after each press. The task included two conditions: no-reset where the progressive delay continues to increase and reset where the progressive delay resets to 0 s after an fixed delay press. Following training, rats were injected with MK-801 (0.06 mg/kg, 0.1 mg/kg, 0.2 mg/kg) or saline before a session. In the no-reset condition, rats on the high dose demonstrated impaired choice behavior characterized by frequent nontask related lever presses during delay periods. In the reset condition, males and females on the high dose made more optimal sequences of choices despite females increasing omitted trials. In both conditions, lever press behavior points to a loss of sensitivity to delay intervals driving the observed effects. Overall, results revealed complex effects of sex and NMDA receptor antagonists on optimal foraging behaviors and overall task responsiveness. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Social defeat (SD) is a well established model that increases addiction vulnerability accompanied by depressive- and anxiety-like behaviors. Environmental enrichment (EE) has been shown to enhance resilience and mitigate stress-induced behavioral alterations. Here, we investigated the protective effects of EE during adolescence, both before and during SD encounters, on stress-induced anxiety, depression and the increased conditioned rewarding effects of a subthreshold cocaine dose in adulthood. We employed the social interaction test (SIT) to categorize mice into resilient and susceptible phenotypes based on depressive-like behaviors. Anxiety was assessed using the elevated plus maze (EPM). EE did not alter the percentage of resilient and susceptible mice (33%-63% in standard housing vs. 46%-54% in EE), nor did it prevent stress-induced anxiety. Only defeated mice housed under standard conditions developed 1.5 mg/kg cocaine-induced conditioned place preference, whereas EE-exposed stressed mice did not acquire cocaine-induced conditioned place preference. Our findings highlight that EE during adolescence serves as a protective factor by promoting the development of a resilient phenotype in adulthood against increased drug reward. However, it was ineffective in counteracting depressive- and anxiety-like behaviors. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Motor imagery is known to be effective for the acquisition of motor skills. Given its covert nature and thus an absence of feedback related to task performance, key to improving overt movement performance, how motor imagery drives skill acquisition is unclear. Here we investigated error-related processes in motor imagery and the role errors may play in driving motor learning. Specifically, we examined (a) the change in self-reported accuracy over time when participants trained on a complex motor skill using motor imagery and (b) if greater change in self-reported accuracy across motor imagery training predicted subsequent physical performance of the motor skill. We hypothesized that self-reported accuracy would increase as a function of time and that greater improvements in self-reported accuracy would predict superior physical performance. Results revealed a significant increase in self-reported accuracy over time. Moreover, changes in self-reported accuracy were highly predictive (R² = 0.43) of physical performance, with participants who showed the greatest improvement in self-reported accuracy also demonstrating greater accuracy during physical performance. These findings support the notion that error-related processes are present and likely play a critical role in learning via motor imagery. We discuss possible mechanisms of error processing in motor imagery, including the updating of internal models. We conclude by proposing a "fusion model" of motor imagery, which posits that motor imagery integrates sensory predictions of movement with a cognitive simulation of movement that permits updating of sensory prediction, in turn facilitating performance improvement and ultimately motor learning. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Reports an error in "Influence of context on extinguished appetitive conditioning in male and female rats" by Samantha K. Moriarty, Shaina L. Weingart, Reihane Abdollahi, Emily A. Rocco, Hannah L. Schoenberg, Neil E. Winterbauer, Donna J. Toufexis, John T. Green and Travis P. Todd (Behavioral Neuroscience, 2025[Aug-Oct], Vol 139[4-5], 193-201; see record 2026-16533-001). Due to an editorial production error, the abbreviation "US" (unconditioned stimulus) was incorrectly changed to "United States." The online version of this article has been corrected. (The following abstract of the original article appeared in record 2026-16533-001.) Extinction is fundamental to adaptive behavior in that it allows organisms to alter previously conditioned behaviors based on the prevailing environmental contingencies. Extinguished responses, however, will renew when the conditioned stimulus is presented outside the extinction context. There has been some suggestion that renewal after extinction of appetitive conditioning is a sex-specific process, with only male rats showing renewal (e.g., Anderson & Petrovich, 2015, 2017, 2018). The purpose of the present experiments was to revisit the role of sex in appetitive renewal, in part because an earlier literature demonstrated renewal in experiments with only female rats (e.g., Brooks & Bouton, 1994). In three experiments, rats underwent appetitive Pavlovian conditioning in Context A, followed by extinction in Context B, and then within-subject renewal testing in both B and A. In Experiment 1a, renewal was present for both male and female rats. In Experiment 1b, the procedure included exposures to Context A during the extinction phase. Once again, renewal was observed in female rats. In Experiment 2, we assessed if cycling hormones contribute to renewal in female rats. To do so we compared intact female rats with ovariectomized female rats, and observed robust renewal in both groups. Our results support the notion that renewal is a general behavioral phenomenon, and is one reason why behavior change may be difficult to sustain (Bouton, 2014). (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Adaptive behavior depends on the ability to predict specific events, particularly those related to rewards. Armed with such associative information, we can infer the current value of predicted rewards based on changing circumstances and desires. To support this ability, neural systems must represent both the value and identity of predicted rewards, and these representations must be updated when they change. Here we tested whether prediction error signaling of dopamine neurons depends on two areas known to represent the specifics of rewarding events, the hippocampus (HC) and orbitofrontal cortex (OFC). We monitored the spiking activity of dopamine neurons in rat ventral tegmental area during changes in the number or flavor of expected rewards designed to induce errors in the prediction of reward value or reward identity, respectively. In control animals, dopamine neurons registered both error types, transiently increasing firing to additional drops of reward or changes in reward flavor. These canonical firing signatures of value and identity prediction errors were altered in rats with ipsilateral neurotoxic lesions of either HC or OFC. Specifically, HC lesions caused a failure to register either type of prediction error, whereas OFC lesions caused abnormally persistent signaling of identity prediction errors and much more subtle effects on signaling of value errors. These results demonstrate that HC and OFC contribute distinct types of information to the computation of prediction errors signaled by ventral tegmental area dopamine neurons. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

The mechanisms responsible for individual differences in cognition are not well understood. This study assessed behavioral performance and magnetic resonance imaging (MRI)-derived brain volumes in male Fischer 344 young (6 months), middle-aged (15 months), and aged (23 months) adult rats and asked two primary questions: Do individual differences in spatial performance predict behavior in other cognitive domains? Are the observed differences in cognition related to the volume of brain areas responsible for these cognitive processes? Several cognitive domains were examined here along with MRI-derived volumetric measures of the hippocampus and neocortex. The tasks assessed spatial reference and working memory, and temporal ordering and spatial location novelty tasks. The hippocampus-dependent spatial version of the Morris watermaze was used to categorize each rat into high, average, and low performers within each age group. When scores on the spatial working memory task were compared to the spatial reference memory task, only young adults showed a positive relationship between performance on these tasks; this relationship was not apparent in the older animals. With respect to MRI measurements, differences were found in total intracranial volume and total brain volume across age, but there were no statistically significant relationships found across age or between cognitive categories in the neocortex or hippocampus cornu ammonis subfields. Three primary conclusions can be drawn: There is large variability in spatial memory across all ages, high performance on one cognitive domain does not necessarily predict high performance on another, and finally, finer structural analyses may be required to identify brain changes responsible for the individual differences observed here. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Early life inflammation has long been associated with increased risk of later neuropsychiatric developmental disorder (NDD) diagnosis in humans. However, despite converging lines of evidence implicating the immune system in NDD etiology combined with reported sex differences in NDD diagnosis rates and the increasingly appreciated role of traditionally immune-associated factors in the sexual differentiation of the brain, a direct link connecting these three processes remains elusive. Here, we sought to characterize the enduring effects of early life inflammation in male and female rats exposed to the viral mimetic polyinosinic:polycytidylic acid (poly(I:C), 5 mg/kg) on Postnatal Day 8 (P8) and P10, a sensitive period we previously identified. We assessed a variety of behaviors-from juvenile social play to adult reward-guided decision making-and recorded from single neurons in nucleus accumbens as rats performed a task commonly used to assess cognitive control. All assessments were performed in the same animals allowing for exploratory factor analysis, which identified five factors that together reveal novel connections between behavioral measures across the lifespan and neural activity patterns. Collectively, this work suggests that viral-mediated inflammation at this developmental timepoint is not a robust risk factor for an NDD-like phenotype in rats. However, factor analysis revealed that sex and early life inflammation shifted two distinct modalities of rat "personality," highlighting the utility of combining modern neuroscience approaches with the study of complex, naturalistic behaviors. Future work should directly test these putative factor associations to determine the extent to which early life behavior may be predictive of adult cognition. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Gonadal hormones (e.g., estradiol and progesterone) influence response to, and preference for, drugs in females; however, how hormonal contraceptives, synthetic hormones that decrease gonadal hormone levels, affect drug preference is not known. The current experiment investigated whether oral administration of levonorgestrel (LNG), a synthetic progestin used in hormonal contraceptives, would lead to a reduction in amphetamine (AMPH) preference. Female rats were tested for their AMPH preference over 3 days (which also served as extinction sessions) after receiving oral administration of LNG (250 μg, 500 μg, or 2 mg) or during an estrous cycle stage associated with higher levels of gonadal hormones (i.e., proestrus/estrus). Our results show that AMPH preference was reduced for females on 500 μg and 2 mg of LNG across extinction sessions. Interestingly, only the 2 mg LNG dose led to a disruption in the naturally occurring estrous cycle. Uterine horn width, an index of estrogen exposure, was decreased in all LNG groups, but only the 500 μg and 2 mg LNG groups showed suppression of gonadal hormones, suggesting that both doses are sufficient for contraceptive use in rats. Our study demonstrates an effective and noninvasive oral LNG administration method in a rat model and further shows reduced AMPH preference by LNG. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Gaze is one of the primary experimental measures for studying cognitive development, especially in preverbal infants. However, the field is only beginning to develop a principled explanatory framework for making sense of the various factors affecting gaze. We approach this issue by addressing infant gaze from first principles, using rational information gathering. In particular, we revisit the influential descriptive account of Hunter and Ames (1988), which posits a set of regularities argued to govern how gaze preference for a stimulus changes with experience and other factors. When the Hunter and Ames's (1988) model is reconsidered from the perspective of rational information gathering (as recently also proposed by other authors), one feature of the model emerges as surprising: that preference for a stimulus is not monotonic with exposure. This claim, which has at least some empirical support, is in contrast to most statistical measures of informativeness, which strictly decline with experience. We present a normative, computational theory of visual exploration that rationalizes this and other features of the classic account. Our account suggests that Hunter and Ames's (1988) signature nonmonotonic pattern is a direct manifestation of a ubiquitous principle of the value of information in sequential tasks, other consequences of which have recently been observed in a range of settings including deliberation, exploration, curiosity, and boredom. This is that the value of information gathering, putatively driving gaze, depends on the interplay of a stimulus' informativeness (called gain, the focus of other rationally motivated accounts) with a second factor (called need) reflecting the estimated chance that information will be used in the future. This computational decomposition draws new connections between infant gaze and other cases of exploration, and offers novel, quantitative interpretations and predictions about the factors that may impact infant exploratory attention. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Environmental threats are typically encountered when animals are searching for food and other necessities. Adaptive behavior must balance competition between fear behavior and reward seeking. We gave rats local neuronal deletions of the ventral pallidum (VP) or specifically deleted paraventricular thalamic nucleus (PVT) neurons projecting directly to the VP. Rats were then assessed in a conditioned suppression procedure in which cues predicting unique foot shock probabilities were presented during, but independent from, reward seeking. Foot shock introduction generally suppressed reward seeking in rats, and recovery from shock introduction was facilitated in rats with VP or PVT → VP pathway deletions. Discriminative fear was observed in controls, and this fear responding reduced over a single extinction session. VP deletion enhanced extinction fear responding, and PVT → VP pathway deletion abolished within-session fear reductions. The results demonstrate the VP and its inputs from the PVT shape reward seeking in threat settings and govern fear extinction responding. (PsycInfo Database Record (c) 2025 APA, all rights reserved).