Can Endogenous Attentional Orientation Direct Inhibition Of Return?

Inhibition of return(IOR)refers to a bias against attending to and/or detecting visual stimuli at recently attended locations,and its mechanism has always been the core of this field. Recently, Taylor and Klein(2000) put forward their famouse theory(Taylor & Klein, 2000 Journal of Experimental tended to: the Human Perception and Performance was 39-1656) —— the theory of two flavours —— suggested that there are two different kinds of IOR according to the conditions of oculomotor system. Specifically, When the oculomotor system is “actively suppressed”, IOR affects input processes(the perception/attention flavor,contain endogenous and exogenous attention), whereas when the oculomotor system is “engaged”, IOR affects output processes(the motor flavor). While, previous studies proved that endogenous attentional orientation erther cannot affect perception, or result in the input IOR. For this debate,used the eye-link and brain electrical technique,this study verified the results of Taylor and Klein(2000), further to explore the role of endogenous attentional orientation in IOR, and analysis of its causes and effects.This study included four experiments, the first three experiments adapt target-target paradigm, the fourth adapts cue-target paradigm.In the first three experiments,paticipants were required to press keyboard button manually when S1(the first stimulate) and /or S2(the second stimulate)appeard. Avoiding eye movement interfer experiments, the instructions reminded paticipants to fix their eyes on the fixation. Eyelink 2000 was used in the first(E1),second(E2) and fourth(E4) experiments,and ERP was used in the thired one(E3) to monitor the eyes condition.The aim of E1 is to examine whether the join of the secondary cue could cause endogenous attention,which come into being the IOR. The results showed that under the two conditions(with and without secondary cue)there were not IOR,and the second cue could only alarm attention.That’s to say the input IOR,found by Taylor and Klein(2000),are not caused by the join of the secondary cue.There are two parallel experiments, E2 a and E2 b,to examine whether the inhibition found in Taylor and Klein(2000) is NCE. Recently, studies have shown that the result of Taylor and Klein(2000) existed NCE, which inhibite the exogenous target. In E2, the independent variables were types of S2(endogenous and exogenous) and targets’ properties(repeated and switched). The two types of S2 were mixed in E2 a and blocked in E2 b. Results showed that in E2 a both kinds of S2 were inhibited, while in E2 b, in endogenous condition there was no inhibitory effect. These suggested the manual located method in ours can’t cause an NCE effect.Experiment 3 investigated the reason of inhibition caused by endognous attentional oritation. A frequently observed phenomenon in the area of task switching was responserepetition costs(RRC), refered to the phenomenon that the responding is slower and/or less accurate when the response from the previous trial repeats, compare to shifts.Though the behavioral results between IOR and RRC are samilar,there are separation in ERP, with P3 effect in the formar and P1 effect in the latter. This experiment recorded behavior and ERP reactions after different SOA(200, 700 ms). In the long SOA,there are inhibitory effect and P3 effect. In other words, this inhibitory effect is RRC. Above all, we conculded that the inbihition caused by endognous attention is RRC not IOR.E4 investigated whether the endognous attention caused buy the other way, highly predictive arrows(80%), can affect IOR.The design was similary with E3 disbide that the particepant were told that the effectiveness of arrow is 80%, and just answer to exogenous S2.With the faster reaction to S2 in vailed cues than in unvailed cues, E4 illustrated that endognous attention caused by highly predictive arrows cannot affect IOR as well.To sum up, this study concluded that :(1) In the target- target paradigm, the inhibition of exogeous target, which caused by endogeous cue,is expectation supression but not IOR.(2) Endogenous attentional orientation cannot direct IOR.( 3) Without exogeous cues, endogenous attention could not affect perception.(4) The endogenous attention are not contained in the input IOR.