A 2026 eLife study recorded 3,881 lateral orbitofrontal cortex units in rats and found that prior cocaine use made the OFC over-distinguish task positions that controls treated as functionally equivalent. The headline result was not gross task failure: cocaine-experienced rats still performed the odor task, but their OFC ensembles showed higher S1-vs.-S2 decoding than sucrose …
A 2026 longitudinal MRI preprint involving 54 people with Friedreich ataxia and 57 controls found 3 biologically interpretable progression subtypes: microstructure-dominant, macrostructure-dominant, and minimal/no progression.1 The clusters make biomarker heterogeneity visible at the research level, while the classifier remains too early to assign individual patients to treatment paths. Research Highlights 3 MRI progression subtypes emerged: …
A 2026 fMRI meta-analysis of 11 studies found a narrow anxious-depression signal: 829 anxious-depression patients differed from 681 non-anxious MDD patients in left middle temporal gyrus activation (SDM-Z = 2.046, p = 0.020), while healthy-control contrasts centered on the anterior commissure and right middle frontal gyrus. The calibrated interpretation is not “amygdala and insula hyperactivity …
A 2026 male-mouse study found that 30 mg/kg dexamethasone for 5 days increased light-phase wakefulness (t13 = 4.122, p = 0.0012), decreased NREM sleep (t13 = 4.412, p = 0.0007), and amplified orexin-neuron activity during NREM-to-wake transitions (F1,9 = 6.941, p = 0.0272). The result points to orexin-linked hyperarousal as a testable explanation for steroid-induced …
A 2026 Nature mouse study found that basolateral amygdala astrocyte Ca2+ signals tracked fear retrieval and extinction, then showed causality: 3 mg/kg CNO manipulations of astrocyte DREADDs pushed early-extinction freezing in opposite directions while both disrupting later extinction retrieval.1 Research Highlights Astrocytes tracked fear state: after 3 tone-shock pairings and 2 days of 25 cue-only …
Standard memory testing can tell a multiple-sclerosis (MS) patient that recall is normal after 30 minutes while missing a deficit that appears days later. Jansen et al. tested that exact blind spot in 62 MS patients and 65 matched controls: 7-day/30-minute recall ratios were lower in MS on both verbal-list recall (0.64 vs. 0.78, p …
Whether alcohol, cocaine, nicotine, and cannabis damage the same brain regions or different brain regions has been hard to settle in the addiction-imaging literature. A 2026 ENIGMA Addiction analysis by Georgiadis et al. — pooling 4,733 brains across 51 sites — now has an answer. Research Highlights Across 2,782 people with substance use disorder (SUD) …