a1 Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD 21205. firstname.lastname@example.org
Two major themes have emerged in the commentaries elicited by the target articles that concern cerebellar long-term depression (LTD) (CRÉPEL, VINCENT, and LINDEN). First, is a lively debate concerning the potential role of a nitric oxide/cGMP cascade in cerebellar LTD induction. Second is a much broader issue relating to the interchange of information between cerebellar physiologists concerned with mechanisms at a cellular and synaptic level and those working at the level of systems physiology, behavior, or modeling. What contributions can cellular physiologists make to the study of motor learning? Cellular physiologists can provide testable hypotheses to help determine if these synaptic phenomena do underlie particular behaviors (e.g., if cerebellar LTD underlies vestibulo-ocular reflex [VOR] adaptation or eyeblink conditioning, then blockade of cerebellar LTD via, say, mGluRl inhibition, should interfere with these forms of motor learning). In addition, we can provide descriptive parametric information about basal synaptic function and use-dependent synaptic modifications that can constrain the range of models proposed to underlie a given behavior (e.g., are the timing constraints on LTD induction consistent with VOR adaptation or eyeblink conditioning?).