Front Integr Neurosci. 2014 Feb 11;8:13. doi: 10.3389/fnint.2014.00013. eCollection 2014.
Frontiers in integrative neuroscience
Münire Özlem Cevik
PMID: 24574983 PMCID: PMC3920081 DOI: 10.3389/fnint.2014.00013
In this brief review, I argue that the impact of a stimulus on behavioral control increase as the distance of the stimulus to the body decreases. Habituation, i.e., decrement in response intensity repetition of the triggering stimulus, is the default state for sensory processing, and the likelihood of habituation is higher for distal stimuli. Sensitization, i.e., increment in response intensity upon stimulus repetition, occurs in a state dependent manner for proximal stimuli that make direct contact with the body. In Pavlovian conditioning paradigms, the unconditioned stimulus (US) is always a more proximal stimulus than the conditioned stimulus (CS). The mechanisms of associative and non-associative learning are not independent. CS-US pairings lead to formation of associations if sensitizing modulation from a proximal US prevents the habituation for a distal anticipatory CS.
Keywords: Drosophila melanogaster; dopamine; habituation; mushroom bodies; olfactory conditioning; proboscis extension response