This seminar will begin at 4:00 pm at the Jerome L. Greene Science Center on Columbia University’s Manhattanville campus (L7-119). Light refreshments will be available starting at 3:30 pm.
This month's speakers:
Anders Nelson (Costa lab): "Structural and Functional Coordination of Corticospinal and Corticostriatal Pathways"
Voluntary movement emerges from neuronal activity distributed across a range of interconnected motor control structures, including motor cortex, the basal ganglia, and the spinal cord. How structural and functional unity is maintained between these regions is unclear, but may depend on the expansive network of axonal collaterals that corticospinal neurons project throughout the brain, most notably to the striatum. My research aims to characterize the synaptic organization of these axon collaterals in the striatum, and how movement-related signals generated by corticospinal neurons are transmitted to two opponent populations of striatal projection neurons.
James O’Sullivan (Mesgarani lab): "Hierarchical Encoding of Attended Speech in Human Auditory Cortex"
In a multi-talker scenario, humans can focus their attention on just one speaker and dynamically switch their attention with ease, even without spatial information. Research into how the brain solves this complex problem suggests that attended and unattended speech are co-represented at early stages of cortical processing, with a selective representation of attended speech emerging later. Invasive recordings using electrocorticography (ECoG) have revealed that this selective representation is present in superior temporal gyrus (STG), which is a non-primary auditory cortical region. It is unknown how multi-talker speech is represented in primary auditory cortex, and whether or not it is modulated by attention. If this area represents the mixture, then what transformations and processes occur such that a selective representation of attended speech can emerge in STG? Here we leverage the capability of recording invasively in humans, which allows us to explore the representation of attended and unattended speech along the auditory cortical hierarchy from primary to non-primary auditory cortices.