Learn More
The cortical representation of the sensory environment is continuously modified by experience. Changes in spatial (receptive field) and temporal response properties of cortical neurons underlie many forms of natural learning. The scale and direction of these changes appear to be determined by specific features of the behavioral tasks that evoke cortical(More)
Over the last 50 yr, environmental enrichment has been shown to generate more than a dozen changes in brain anatomy. The consequences of these physical changes on information processing have not been well studied. In this study, rats were housed in enriched or standard conditions either prior to or after reaching sexual maturity. Evoked potentials from(More)
Cortical responses are adjusted and optimized throughout life to meet changing behavioral demands and to compensate for peripheral damage. The cholinergic nucleus basalis (NB) gates cortical plasticity and focuses learning on behaviorally meaningful stimuli. By systematically varying the acoustic parameters of the sound paired with NB activation, we have(More)
Temporal features are important for the identification of natural sounds. Earlier studies have shown that cortical processing of temporal information can be altered by long-term experience with modulated sounds. In a previous study, we observed that environmental enrichment dramatically increased the response of cortical neurons to single tone and noise(More)
We characterized the 2F1-F2 distortion product reflected in the human frequency-following response (FFR). In the first experiment, we evaluated the input-output growth functions of the distortion product at 2F1-F2 (FFR-DP) for three primary pairs. In the second experiment, we tested the effect of primary tone level variation on the FFR-DP. The results for(More)
The rat auditory cortex is divided anatomically into several areas, but little is known about the functional differences in information processing between these areas. To determine the filter properties of rat posterior auditory field (PAF) neurons, we compared neurophysiological responses to simple tones, frequency modulated (FM) sweeps, and amplitude(More)
Sensory experience alters the functional organization of cortical networks. Previous studies using behavioral training motivated by aversive or rewarding stimuli have demonstrated that cortical plasticity is specific to salient inputs in the sensory environment. Sensory experience associated with electrical activation of the basal forebrain (BasF) generates(More)
The mammalian auditory system evolved to extract meaningful information from complex acoustic environments. Spectrotemporal selectivity of auditory neurons provides a potential mechanism to represent natural sounds. Experience-dependent plasticity mechanisms can remodel the spectrotemporal selectivity of neurons in primary auditory cortex (A1). Electrical(More)
Classical conditioning paradigms have been shown to cause frequency-specific plasticity in both primary and secondary cortical areas. Previous research demonstrated that repeated pairing of nucleus basalis (NB) stimulation with a tone results in plasticity in primary auditory cortex (A1), mimicking the changes observed after classical conditioning. However,(More)
Theories of temporal coding by cortical neurons are supported by observations that individual neurons can respond to sensory stimulation with millisecond precision and that activity in large populations is often highly correlated. Synchronization is highest between neurons with overlapping receptive fields and modulated by both sensory stimulation and(More)