Editing Eyeblink conditioning (section)

==CS-US contingency==

The order in which stimuli are presented is an important factor in all forms of [[classical conditioning]]. [[Forward conditioning]] describes a presentation format in which the CS precedes the US in time. That is, from the perspective of the research subject, experiencing the US is ''contingent'' upon having just experienced the CS. EBC is usually, but not always, conducted in this manner. Other stimulus [[contingencies]] include [[backward conditioning]], in which US comes before CS, and [[simultaneous conditioning]], in which CS and US are presented at the same time. In any case, the time between CS onset and US onset is the [[interstimulus interval]] (ISI). Animals are usually trained with a shorter ISI than humans, which can make interspecies comparisons difficult.<ref>{{cite journal|last1=Kjell|first1=Katarina|date=December 3, 2018|title=A Longer Interstimulus Interval Yields Better Learning in Adults and Young Adolescents|journal=Front Behav Neurosci|volume=12|pages=299|doi=10.3389/fnbeh.2018.00299|pmc=6286956|pmid=30559655|doi-access=free}}</ref> 

===The delay and trace procedures===

In delay EBC, the CS onset precedes the US onset and the two stimuli overlap and coterminate, with the stimuli converging in the cerebellar cortex and interpositus nucleus.<ref>{{cite book |last1=Takehara |first1=K |title=The Anatomy and Physiology of Eyeblink Classical Conditioning in: Behavioral Neuroscience of Learning and Memory |volume=37 |date=2016 |publisher=Springer, Cham |pages=297–323 |doi=10.1007/7854_2016_455 |pmid=28025812 |chapter=The Anatomy and Physiology of Eyeblink Classical Conditioning |series=Current Topics in Behavioral Neurosciences |isbn=978-3-319-78755-8 }}</ref> In the trace EBC, the CS precedes the US and there is a stimulus free period (trace interval) between CS offset and US onset. While both of these procedures require the [[cerebellum]], the trace procedure also requires the [[hippocampus]] and medial prefrontal cortex.<ref>Takehara, K., Kawahara, S., & Kirino, Y. (2003). Time-dependent reorganization of the brain components underlying memory retention in trace eyeblink conditioning. ''J. Neurosci.'', ''23'':9896–9905.</ref><ref>Squire, L. R., Stark, C. E. L., & R. E. Clark (2004). The medial temporal lobe. ''Annu. Rev. Neurosci.'' ''27'':279–306.</ref>