Precise Memory is Predicted by Learning-Induced Sensory System Neurophysiological Plasticity

Despite identical learning experiences, individuals differ in the memory formed of those experiences. Memory formed with sensory specificity determines its utility for selectively cueing subsequent behavior, even in novel situations. If an individual forms generalized memory, then there is potential for novel sensory cues to interfere with accurate behavioral performance. Here, a rodent model of auditory learning capitalized on individual differences in learning-induced auditory neuroplasticity to identify and characterize neural substrates for sound-specific (vs. general) memory of the training signal’s acoustic frequency. Animals with naturally or pharmacologically induced signal-“specific” memory revealed behaviorally, exhibited long-lasting signal-specific neurophysiological plasticity in auditory cortical and subcortical evoked responses, while learning-induced changes were not detected in animals with “general” memories. Individual differences validated this brain-behavior relationship, such that the degree of change in neurophysiological responses could be used to determine the precision of memory formation.