Environmental enrichment (EE) reduces vulnerability to multiple drugs of abuse, yet its impact on fentanyl use and relapse-like behavior remains unclear. Here, we tested whether long-term, non-social, object-based EE alters fentanyl self-administration, extinction, and stress-induced reinstatement in male and female rats. Rats were individually housed in either standard non-enriched (NE) conditions or in EE cages containing a rotating set of novel objects beginning at least three days prior to self-administration. EE did not impact acquisition of fentanyl self-administration but reduced fentanyl intake during maintenance of self-administration and reduced the persistence of drug-seeking in extinction. Following extinction, yohimbine robustly reinstated drug-seeking behavior in NE rats but reinstatement in EE rats was markedly attenuated, indicating reduced sensitivity to stress-induced relapse triggers. Circulating corticosterone levels were lower in EE rats across the experiment and were positively correl...

Olfactory anhedonia and heightened aversion to unpleasant odors are well-documented features of depression in humans, yet the neural mechanisms linking chronic stress to altered olfactory perception remain poorly understood. We used the Unpredictable Chronic Mild Stress (UCMS) paradigm to examine how chronic stress affects olfactory avoidance behavior and glial cell morphology across multiple olfactory brain regions in male and female mice. UCMS-treated mice showed increased avoidance of aversive odorants in an odorized light/dark box assay, consistent with heightened aversive reactivity to odors following chronic stress. Using immunohistochemistry, we assessed microglial morphology and astrocyte density across six olfactory and limbic brain regions. Chronic stress produced region-specific glial remodeling: astrocyte counts were selectively elevated in the medial amygdala, and microglial process complexity was increased in the anterior olfactory nucleus and anterior piriform cortex. Microglial morphologica...

Despite major advances in brain-computer interfaces (BCIs), decoding high-level language representations prior to speech remains challenging. While prior efforts have primarily focused on acoustic or articulatory features, how semantic categories are decoded in time and space remains unclear. Here, we investigated how semantic representations unfold over time by analyzing high-gamma (HG, 70–170 Hz) electrocorticography (ECoG) signals from twenty subjects (7 females and 13 males) performing a word-reading task involving body- and non-body-related words. HG activity was examined from word presentation to 500 ms, capturing the pre-speech window. Group-level time-resolved decoding, pooling features across subjects within each Brodmann area (BA), revealed significant classification accuracy above chance in both hemispheres (p<0.05, FDR-corrected). In the left hemisphere, peak-performing BAs followed a frontal–temporal–occipital–parietal cascade: dorsolateral prefrontal cortex (dlPFC) (50 ms), inferior temporal ...

Extinction-reinstatement paradigms have been used to study reward-seeking for both food and drug rewards. The nucleus accumbens (NAc) is of particular interest in reinstatement due to its ability to energize motivated behavior. Previous work found that suppression of neuronal activity or dopamine signaling in NAc reduces reinstatement of food-seeking. Here we used fiber photometry and sensor multiplexing (red-shifted dopamine sensor and genetically-encoded calcium indicator) to measure dopamine and calcium in NAc core of male and female rats on each day of an extinction-reinstatement paradigm with food reward to determine how signals vary across task phases. During self-administration training, we detected positive dopamine transients that initially followed lever-pressing but moved earlier in time as training progressed. A post-press dopamine decrease also emerged with training. For calcium, a decrease from baseline occurred after the press and became more prominent across training. Both patterns were red...

The flexible control of working memory (WM) requires prioritizing immediately task-relevant information while maintaining information with potential future relevance in a deprioritized state. Using double-serial retrocuing (DSR) with simultaneous EEG recording, we investigated how single pulses of transcranial magnetic stimulation (spTMS) to right intraparietal sulcus impacts neural representations of unprioritized memory items (UMI), relative to irrelevant memory items (IMI) that are no longer needed for the trial. Twelve human participants (8 female) performed DSR plus a single-retrocue task, while spTMS was delivered during delay periods. Multivariate pattern analysis revealed that spTMS restored decodability of the UMI concurrent with stimulation, and that of the IMI several timesteps later, after the evoked effects of spTMS were no longer present in the EEG signal. This effect was carried by the alpha (8-13 Hz) and low-beta (13-20 Hz) frequency bands. Analyses of the raw EEG signal showed two effects ...

Many of the brain’s most intriguing mechanisms are difficult, if not impossible, to measure directly. For this reason, neuroscientists create artificial models of the brain, inspired by real biology, and study in tandem with carefully directed measurements. Computational neuroscience merges biology’s search for brain mechanisms with an engineering-like pursuit of realistic models. Using approaches from engineering and the physical sciences, alongside analysis of data collected from real brains, the field is poised to answer big questions about cognition and what goes wrong in disease.

Join experienced SfN annual meeting attendees Janice Naegele and Veronica Galvin to learn tips for creating a Neuroscience 2023 experience tailored to your personal and professional goals.

Neurosurgeons have unique access to the human brain. In just the last 10 years, neurosurgical techniques have advanced rapidly such that opportunities to study neural activity and neuromodulation in acute and chronic settings have multiplied. This session will discuss how a background in nonhuman primate neurophysiology has translated into work studying both pathological and normal human brain function across movement disorders, epilepsy, and intractable psychiatric disease.

Neuromodulators influence communication across brain areas by shaping the activity of neurons as well as the strength and plasticity of their synapses, ultimately promoting behavioral switching. This session will review a research journey from ion channel neuromodulation via receptors located on anatomically different pathways and in distinct cellular compartments, to the temporal resolution of behaviorally relevant neuromodulatory signals.

Spatial transcriptomics was the first method to provide unbiased whole transcriptome analysis with spatial information from tissue. Since its publication in 2016, the method has been used in multiple biological systems and represents the most widely used spatial transcriptomics platform (aka Visium). The method was featured in Nature Methods' "Method of the Year 2020." This presentation will cover the exciting expansion into new spatial modalities to explore tissue ecosystems.