Individuals respond faster to presentations of bisensory stimuli (e.g. audio-visual targets) than to presentations of either unisensory constituent in isolation (i.
View Article and Find Full Text PDFBrain state fluctuations modulate sensory processing, but the factors governing state-dependent neural activity remain unclear. Here, we tracked the dynamics of cortical extracellular K concentrations ([K]) during awake state transitions and manipulated [K] in slices, during visual processing, and during skilled motor execution. When mice transitioned from quiescence to locomotion, [K] increased by 0.
View Article and Find Full Text PDFRett syndrome (RTT), a rare neurodevelopmental disorder caused by mutations in the MECP2 gene, is typified by profound cognitive impairment and severe language impairment, rendering it very difficult to accurately measure auditory processing capabilities behaviorally in this population. Here we leverage the mismatch negativity (MMN) component of the event-related potential to measure the ability of RTT patients to decode and store occasional duration deviations in a stream of auditory stimuli. Sensory memory for duration, crucial for speech comprehension, has not been studied in RTT.
View Article and Find Full Text PDFGenetic screens in Drosophila melanogaster and other organisms have been pursued to filter the genome for genetic functions important for memory formation. Such screens have employed primarily chemical or transposon-mediated mutagenesis and have identified numerous mutants including classical memory mutants, dunce and rutabaga. Here, we report the results of a large screen using panneuronal RNAi expression to identify additional genes critical for memory formation.
View Article and Find Full Text PDFComprehensive knowledge of the brain's wiring diagram is fundamental for understanding how the nervous system processes information at both local and global scales. However, with the singular exception of the C. elegans microscale connectome, there are no complete connectivity data sets in other species.
View Article and Find Full Text PDFPsychological studies in humans and behavioral studies of model organisms suggest that forgetting is a common and biologically regulated process, but the molecular, cellular, and circuit mechanisms underlying forgetting are poorly understood. Here we show that the bidirectional modulation of a small subset of dopamine neurons (DANs) after olfactory learning regulates the rate of forgetting of both punishing (aversive) and rewarding (appetitive) memories. Two of these DANs, MP1 and MV1, exhibit synchronized ongoing activity in the mushroom body neuropil in alive and awake flies before and after learning, as revealed by functional cellular imaging.
View Article and Find Full Text PDF