Topic: stratum lacunosum moleculare

Remembering and responding to aversive events is a crucial evolutionarily conserved behavior. In mammals, regulation of contextual fear memories depends on both medial prefrontal cortex (mPFC), key for extinguishing non-salient fear responses, and dorsal hippocampal CA1 (dCA1), key for encoding contextual memories. However, there is no direct mPFC to CA1 path, leaving unclear how these regions coordinate. A potential route is through the Nucleus Reuniens (NR), a higher-order thalamic region well-connected to emotional regulation areas. NR is driven by mPFC and sends an excitatory monosynaptic

Brain rhythms have been postulated to play central roles in animal cognition. A prominently reported dichotomy of hippocampal rhythms exclusively assigns occurrences of theta-frequency (4–12 Hz) oscillations to exploratory behavior and rapid eye movement (REM) sleep, and of ripple-frequency (120–250 Hz) oscillations to wakeful rest and non-REM sleep. However, due to their differential expression across hippocampal strata, reports of such exclusivity demand validation through simultaneous multi-strata recordings. Here, we assessed co-occurrence of the two oscillations in multi-channel recording