Can Munal-response Direct Output-based IOR?

As explored in a typical cue-target paradigm,when stimulus-onset asynchrony(SOA)is long(>300ms),inibition of return(IOR)refers to the phenomenon of slower response times(RTs)to previously cued location.The more important on IOR is its mechanism.One theory is that IOR is input-based,such as attention deficit or repeated sensory inhibition at the cued location.Another is that IOR is output-based,reflecting a response bias.The mechanism has been hotly debated,even some think IOR has attention and motor components simultaneously.With the development of the theory,Taylor and Klein(2000)put forward the theroy of two flavors.They think IOR has two independent pathway: input and output.They use 6 experiments to investigated the cause and effect.Cue(S1)and target(S2)are present in order.Its design is 2×2×2 within-subjects factorial combination of S1(peripheral or central),S2(peripheral or central),and location signaled by S2 relative to S1(different or same).Each participant performed all six S1-S2 response combinations: no-response-manual,manual-manual,saccadic-manual,no response-saccadic,manual-saccadic,saccadic-saccadic.The result shows that,one form of IOR impairs response to peripheral stimuli but only when eye movements are not made.This can be seen for the no response-manual and manual-manual combinations,for which IOR is generated by both central and peripheral S1 but affected only RTs to peripheral S2.The other form of IOR impaired responding to both central and peripheral S2 but only when eye movements are made.Whereas,Ivanoff and Klein(2000),Ivanoff and Klein(2003),Ivanoff and Klein(2004),Taylor and Ivanoff(2003),in the same experiment condition(ignore cues and make manual reaction to peripheral targets),find different results.In this condition,they find output-based IOR.It's different from the theory of two flavors.By analyzing,we find the main factor is that whether there is eye-movement monitoring.Our study is to investigate IOR mechanism by using eye-link 2000,the resolution of the screen is 1024×768.Our goal is to find the reason of this phenomenon and to perfect the theory of two flavors.In experiment 1,we firstly repeat previous result.Then we will find the reason of this phenomenon-whether active eyemovement system unconsiously when manualling.Its design is 2×2 within-subjects factorial combination of cue(cued or uncued),and SOA(465ms or 1050ms).The results show that: obvious output-based IOR is found in the two SOA.Eyemovmet activation includes executing a saccadic and planning a saccadic.Though we can't measure saccadic planning,we find obvious eyemovement in 93.75% trials.It is enough to prove that eyemovement system has been activated.Therefore,we draw the conclusion that,in the experiment,participants have actived the eyemovement system unconsciously and it's the nature of the output-based IOR.That said,it accords with the theory of two flavors.In experiment 2,we investigate which sub-system is activited,specificly,finishing the separation of reflective eyemovement system and endogenous eyemovement system.As we all know,antisaccadic task can active endogenous eyemovement system.In this condition,if we can't find output-based IOR,we can judge it is reflective eyemovement system that leads to output-based IOR in return.Its design is 2×2 within-subjects factorial combination of cue(cued or uncued),and cue task type(ignore or antisaccadic).The results show that: when ignore cue,there is output-based IOR;when making antisaccade to cue,there is no IOR.Therefore,activing reflective eyemovement system is the nature of output-based IOR.In experiment 3,we investigate whether activing reflective eyemovement system has an influence on central traget.Generally speaking,central target only reveal output-based IOR when eyemovement is actived.Its design is 2×2 within-subjects factorial combination of cue(cued or uncued),and SOA(465ms or 1050ms).The results show that: there is no IOR on both condition.All in all,we can draw the conclusion that:(1)activating the eyemovement system is the nature of output-based IOR,it is for the two flavors theroy.(2)More specificly,activing reflective eyemovement system is the nature of output-based IOR.(3)activating or forbidding the reflective eyemovement system plays a role in seperating the two IOR.(4)When activating reflective eyemovement system unconciously,there is no impact on central targets.