Behavioral neuroscience最新文献

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).

Early exposure to stress is associated with biological processes that precede cellular senescence and an increased risk of age-related diseases. Adolescence is a period of heightened susceptibility to social environment-related stressors. This developmental stage is also associated with the onset of psychiatric disorders and the adoption of behaviors that can affect long-term health trajectories. In this review, we aimed to assess the progress of rodent research on the relationship between adolescent social stress and later disease-related sequels and cellular senescence. We present a synthesis of 35 peer-reviewed articles indexed in PubMed before July 2025, selected from a web search based on the terms (social stress) AND (senescence OR DNA damage OR telomere OR inflammation) AND (adolescence OR juvenile OR youth OR early life) AND (mice OR mouse OR murine OR rat OR rodent). Adolescent social stress results in decreased social behaviors and increased anxietylike and depressionlike responses. In addition, enduring alterations in physiological responses to acute stress challenges and broad sequelae on neural, cardiovascular, endocrine, and gastrointestinal systems associated with inflammation were found. Sex differences in stress susceptibility were observed across all domains. However, despite the theoretical framework linking stress to aging, our synthesis reveals that direct evidence regarding telomere dynamics and DNA damage in this specific developmental window remains limited in rodent research. Consequently, this review provides an overview of biological mechanisms linking psychosocial stress during adolescence to chronic disease states while identifying the scarcity of direct senescence data as an important gap for future investigation. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Hospitalizations and deaths related to mental health disorders have increased in recent decades, highlighting the need for improved understanding of the neurocircuitry underlying cognitive dysfunction. Dysfunction in neural coordination between the hippocampus (HPC) and prefrontal cortex (PFC) is widely reported to be a signature of many mental health disorders. This circuit is crucial for many forms of adaptive behavior, with the nucleus reuniens (RE) of the thalamus hypothesized to be a critical hub that coordinates HPC-PFC interactions in the service of cognition. This study examined the role of the RE in associative memory by assessing the impact of its inactivation in male and female rats performing the Paired Associates Learning task, a touchscreen-based visuospatial memory paradigm with translational relevance for human mental health disorders. Using muscimol inactivation, we found that RE suppression significantly impaired Paired Associates Learning performance, supporting its role in HPC-PFC circuit coordination. Modulating nicotinic receptors in the RE with an agonist also produced significant deficits; however, we did not see any significant behavioral effects with an antagonist. These findings suggest that the RE is critical for Paired Associates Learning task performance, and its functional contribution may be modulated by cholinergic nicotinic signaling, but additional studies are necessary to test the robustness of this observation. Understanding RE's role in cognition may inform therapeutic strategies for psychiatric and neurological disorders characterized by HPC-PFC dysfunction. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Memories are dynamic and can be made vulnerable to disruption upon reactivation, resulting in a long-lasting attenuation of conditioned responses (i.e., cue-dependent amnesia). Traditionally, cue-dependent amnesia has been studied using AAA between-subjects designs, where a memory is trained for context A, reactivated, and tested with the same context. Using contextual fear conditioning in rats and midazolam as the amnestic agent, we have recently observed that amnesia can be observed when memories are reactivated by a generalization stimulus (context B) and tested with the same generalization stimulus (ABB design). However, this amnestic intervention does not affect the fear expression when animals are tested with the original stimulus (ABA design) or a novel generalization stimulus (ABC design). Methodologically, however, evaluating whether amnesia is reversed, rather than simply not expressed, requires tracking changes in responding within the same individuals across contexts and time. This avoids the ambiguity inherent to between-group comparisons, which may confound memory retention with retrieval differences driven by contextual or procedural variability. Here, using an ABB, ABA, and ABC within-subjects design and employing a gold standard amnestic manipulation-protein synthesis inhibition via cycloheximide-the interplay between memory retention and amnesia expression in different contexts was assessed. The results indicate that amnesia is expressed only when cycloheximide-animals are re-exposed to the reactivation context, regardless of when this re-exposure occurs within the experimental timeline. The implications of these findings for a reconsolidation-based account of postreactivation amnesia are discussed. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

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).