?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Dynamic+properties+of+human+visual+evoked+and+omitted+stimulus+potentials&rft.creator=Bullock%2C+T.H.&rft.creator=Karam%C3%BCrsel%2C+Sacit&rft.creator=Achimowicz%2C+Jerzy+Z.&rft.creator=C.%2C+McClune+Michael&rft.creator=Canan%2C+Baar-Eroglu&rft.subject=Behavioral+Biology&rft.subject=Neural+Modelling&rft.subject=Neurology&rft.subject=Neurophysiology&rft.subject=Neurophysiology&rft.description=Visual+evoked+potentials+(VEP)+and+omitted+stimulus+potentials+(OSPs)+are+reexamined+in+scalp+recordings+from+19+healthy+subjects.+The+principal+finding+is+a+distinction+in+form%2C+latency+and+properties+between+OSPs+in+the+conditioning+stimulus+range+%3C2+Hz%2C+used+in+previous+human+studies%2C+and+those+in+the+range+%3E5+Hz%2C+used+in+previous+studies+of+selected+elasmobranchs%2C+teleost+fish+and+reptiles.+We+cannot+find+OSPs+between+2+and+5+Hz.+The+high+frequency+(%22fast%2C%22ca.+6+to+%3E40+Hz)+and+the+low+frequency+(%22slow%2C%22+ca.+0.3-1.6+Hz)+OSPs+have+different+forms+and+latencies+but+both+tend+to+a+constant+latency+after+the+omission%2C+over+their+frequency+ranges%2C+suggesting+a+temporally+specific+expectation.+Fast+OSPs+(typically+N120%2C+P170-230+and+later+components+including+induced+rhythms+at+10-13+Hz)+resemble+an+OFF+effect%2C+and+require+fixation+but+not+attention+to+the+ISI.+Slow+OSPs+(usually+P500-1100)+require+attention+but+not+fixation%3B+they+are+multimodal%2C+unlike+the+fast+OSPs.+Based+on+cited+data+from+fish+and+reptiles%2C+fast+OSPs+probably+arise+in+the+retina%2C+to+be+modified+at+each+subsequent+level.+We+have+no+evidence+on+the+origin+of+slow+OSPs.+In+both+ranges+not+only+large%2C+diffuse+flashes%3B+but+weak%2C+virtual+point+sources+(colored+LEDs)+meters+away+suffice.+They+are+difficult+to+habituate.+Both+require+very+short+conditioning+periods.+The+transition+from+the+single%2C+rested+VEP+to+the+steady+state+response+(SSR)+at+different+frequencies+is+described.+Around+8-15+Hz+in+most+subjects+larger+SSRs+suggest+a+resonance.+Alternation+between+large+and+small+SSR+amplitude+occurs+around+4+Hz+in+some+subjects+and+conditions+of+attention%2C+and+correlates+with+an+illusion+that+the+flash+frequency+is+two+Hz+or+is+irregular.+Jitter+of+the+conditioning+intervals+greatly+reduces+the+slow+OSP+but+only+slightly+affects+the+fast+OSP.+Differences+between+scalp+loci+are+described.&rft.date=1994&rft.type=Journal+(Paginated)&rft.type=PeerReviewed&rft.format=text%2Fhtml&rft.identifier=http%3A%2F%2Fcogprints.org%2F116%2F1%2Fdynamic_human.htm&rft.identifier=++Bullock%2C+T.H.+and+Karam%C3%BCrsel%2C+Sacit+and+Achimowicz%2C+Jerzy+Z.+and+C.%2C+McClune+Michael+and+Canan%2C+Baar-Eroglu++(1994)+Dynamic+properties+of+human+visual+evoked+and+omitted+stimulus+potentials.++%5BJournal+(Paginated)%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F116%2F