Differences between primary auditory cortex and auditory belt related to encoding and choice for AM sounds.

摘要: We recorded from middle-lateral (ML) and primary (A1) auditory cortex while macaques discriminated amplitude-modulated (AM) noise unmodulated noise. Compared with A1, ML had a higher proportion of neurons that encoded increasing AM depth by decreasing their firing rates ("decreasing" neurons), particularly responses were not synchronized to the modulation. Choice probability (CP) analysis revealed A1 activity different during first half test stimulus. In significant CP began before stimulus, remained relatively constant (or increased slightly) greatly within 200 ms lever release. Neurons in behaved similarly, except disappeared stimulus reappeared second prerelease periods. differences between depend on neural response type. (but A1), when was lower nonsynchronized, neurons, monkey more likely report AM. both rate modulation ("increasing" neurons) similar choice-related dynamics A1. These results suggest that, ascending system, there is transformation coding primarily nonsynchronized dual (increasing/decreasing) ML. This sensory accompanied changes timing related choice, suggesting functional attention and/or behavior.