Representation of Auditory Task Components and of Their Relationships in Primate Auditory Cortex.

The current study aimed to resolve some of the inconsistencies in the literature on which mental processes affect auditory cortical activity. To this end, we studied auditory cortical firing in four monkeys with different experience while they were involved in six conditions with different arrangements of the task components sound, motor action, and water reward. Firing rates changed most strongly when a sound-only condition was compared to a condition in which sound was paired with water.

Neuronal Bases of Systemic Organization of Behavior.

Despite the years of studies in the field of systems neuroscience, functions of neural circuits and behavior-related systems are still not entirely clear. The systems description of brain activity has recently been associated with cognitive concepts, e.g.

Neuronal correlates of auditory streaming in the auditory cortex of behaving monkeys.

This study tested the hypothesis that spiking activity in the primary auditory cortex of monkeys is related to auditory stream formation. Evidence for this hypothesis was previously obtained in animals that were passively exposed to stimuli and in which differences in the streaming percept were confounded with differences between the stimuli. In this study, monkeys performed an operant task on sequences that were composed of light flashes and tones.

Neuronal Correlates of Auditory Streaming in Monkey Auditory Cortex for Tone Sequences without Spectral Differences.

This study finds a neuronal correlate of auditory perceptual streaming in the primary auditory cortex for sequences of tone complexes that have the same amplitude spectrum but a different phase spectrum. Our finding is based on microelectrode recordings of multiunit activity from 270 cortical sites in three awake macaque monkeys. The monkeys were presented with repeated sequences of a tone triplet that consisted of an A tone, a B tone, another A tone and then a pause.