Editing Procedural knowledge (section)

== Activation ==
Lashley (1951) proposed that behavioral sequences are typically controlled with central plans, and the structure of the plans is hierarchical. Some evidences also support this hypothesis. Same behaviors can have different functional interpretations depending on the context in which they occur. The same sound pattern can be interpreted differently depending on where it occurs in a sentence, for example, ''there'' and ''their''. Such contextual dependence is only possible with functionally overarching states of the sort implied by hierarchical plans. <ref>{{Cite book|last=Lashley|first=K. S.|title=The problem of serial order in behavior}}</ref> The initiation time of a movement sequence and the inter-response times of the sequence elements can increase with its length.<ref name=":4">{{Cite journal|last1=Rhodes|first1=Bradley J.|last2=Bullock|first2=Daniel|last3=Verwey|first3=Willem B.|last4=Averbeck|first4=Bruno B.|last5=Page|first5=Michael P.A.|date=2004|title=Learning and production of movement sequences: Behavioral, neurophysiological, and modeling perspectives|url=http://dx.doi.org/10.1016/j.humov.2004.10.008|journal=Human Movement Science|volume=23|issue=5|pages=699–746|doi=10.1016/j.humov.2004.10.008|pmid=15589629 |issn=0167-9457|hdl=2144/1921|s2cid=8012945 |hdl-access=free}}</ref> Further, inter-response times can depend on the size of the phrase that is about to be generated. The larger the phrase, the longer the inter-response time.<ref>{{Cite journal|last1=Collard|first1=Ren?|last2=Povel|first2=Dirk-Jan|date=1982|title=Theory of serial pattern production: Tree traversals.|url=http://dx.doi.org/10.1037/0033-295x.89.6.693|journal=Psychological Review|volume=89|issue=6|pages=693–707|doi=10.1037/0033-295x.89.6.693|issn=0033-295X|url-access=subscription}}</ref><ref>{{Cite journal|last1=Rosenbaum|first1=David A.|last2=Kenny|first2=Sandra B.|last3=Derr|first3=Marcia A.|date=1983|title=Hierarchical control of rapid movement sequences.|url=http://dx.doi.org/10.1037/0096-1523.9.1.86|journal=Journal of Experimental Psychology: Human Perception and Performance|volume=9|issue=1|pages=86–102|doi=10.1037/0096-1523.9.1.86|pmid=6220126 |issn=1939-1277|url-access=subscription}}</ref> Such data have been interpreted in terms of decoding or unpacking hierarchical plans into their constituents. Moreover, learning difficulties changes with the easiness of behavioral sequences.<ref>{{Cite journal|last=Restle|first=Frank|date=1970|title=Theory of serial pattern learning: Structural trees.|url=http://dx.doi.org/10.1037/h0029964|journal=Psychological Review|volume=77|issue=6|pages=481–495|doi=10.1037/h0029964|issn=1939-1471|url-access=subscription}}</ref><ref>{{Cite journal|last=Simon|first=Herbert A.|date=1972|title=Complexity and the representation of patterned sequences of symbols.|url=http://dx.doi.org/10.1037/h0033118|journal=Psychological Review|volume=79|issue=5|pages=369–382|doi=10.1037/h0033118|issn=0033-295X|url-access=subscription}}</ref> Finally, long-term learning of skills is naturally characterized by the process of forming ever larger hierarchical units or chunks.<ref name=":4" /> People learn control structures for successively larger units of behavior, with newly learned routines calling up or relying on more elementary routines, like learning to play simple notes before being able to play a piano concerto.<ref>{{Cite journal|last1=Bryan|first1=William Lowe|last2=Harter|first2=Noble|date=1897|title=Studies in the physiology and psychology of the telegraphic language.|url=http://dx.doi.org/10.1037/h0073806|journal=Psychological Review|volume=4|issue=1|pages=27–53|doi=10.1037/h0073806|issn=0033-295X}}</ref>

As for process of behavior plan forming, Rosenhaum et al. (2007) proposed that plans are not formed from scratch for each successive movement sequence but instead are formed by making whatever changes are needed to distinguish the movement sequence to be performed next from the movement sequence that has just been performed.<ref name=":5">{{Cite journal|last1=Rosenbaum|first1=David A.|last2=Cohen|first2=Rajal G.|last3=Jax|first3=Steven A.|last4=Weiss|first4=Daniel J.|last5=van der Wel|first5=Robrecht|date=2007|title=The problem of serial order in behavior: Lashley's legacy|url=http://dx.doi.org/10.1016/j.humov.2007.04.001|journal=Human Movement Science|volume=26|issue=4|pages=525–554|doi=10.1016/j.humov.2007.04.001|pmid=17698232 |issn=0167-9457|url-access=subscription}}</ref> There are evidences found that motor planning occurs by changing features of successively needed motor plans.<ref>{{Cite journal|last1=Rosenbaum|first1=David A|last2=Weber|first2=Robert J|last3=Hazelett|first3=William M|last4=Hindorff|first4=Van|date=1986|title=The parameter remapping effect in human performance: Evidence from tongue twisters and finger fumblers|url=http://dx.doi.org/10.1016/0749-596x(86)90045-8|journal=Journal of Memory and Language|volume=25|issue=6|pages=710–725|doi=10.1016/0749-596x(86)90045-8|issn=0749-596X|url-access=subscription}}</ref> Also, Rosenhaum et al. (2007) found that even single movements appear to be controlled with hierarchically organized plans, with starting and goal postures at the top level and intermediate states comprising the transition from the starting to the goal at the lower level.<ref name=":5" />