English Words Are Processed Like Objects

English Words Are Processed Like Objects Gavin F. Revie (G.F.Revie@dundee.ac.uk) Yuki Kamide (Y.Kamide@dundee.ac.uk) School of Psychology, University of Dundee, Dundee, UK, DD1 4HN Abstract This experiment sought to explore the theory that familiar English words are processed similarly to objects. To do this, we looked for object-based attentional facilitation where cues in a different location to the target still facilitate target detection as long as they are inside the same object. Participants were shown two English words in an array, and cues and targets were embedded inside them. Reaction times for target detection were measured. It was found that in horizontally presented English words, cues presented in a different location to the target still facilitated target detection if they occurred inside the same word. This was not the case for vertically oriented words. It was concluded that familiar words in a familiar orientation are indeed processed in a similar way to objects. These findings may be indicative that the cortical networks that evolved for object processing are also involved in the processing of words. Keywords: object based; attention; reading; Introduction It has been long understood that humans are capable of focussing their visual attention in one place in preference over another. This is commonly described as spatial attention. However, humans also have the capacity to allocate their attention to a particular object regardless of where it happens to be located (Blake & Sekuler, 2006). This is known as object based attention. In day to day scenarios these two types of visual attention will interact and overlap. However, how object based attention contributes to the process of reading (if at all) is not well understood. Egly, Driver, & Rafal, (1994) conducted a study on attention within objects. Participants saw a 2x2 array with a fixation point in the middle. The array contained 2 rectangular shapes which each spanned two of the quadrants. These shapes could be oriented with either both of them vertical or both of them horizontal. Within the individual cells of the array very brief cues and targets were presented. Participants had to detect the onset of a grey target square following presentation of a 100ms brightening cue. They had 3 possible cuing conditions in their experiment. In the valid condition, the cue and the target would appear in the same location. In the invalid within-object condition, the cue and the target were in different locations, but still within the same object. In the invalid different-object condition, the cue and the target were in different locations and within different objects. The targets in both of the invalid conditions were the same distance from their cue, and they were equally often oriented vertically as horizontally. The corner to corner diagonal separation of the cue and target was not used due to non-equal distance. Egly et al. (1994) successfully manipulated the deployment of attention. The valid trial types were consistently responded to the fastest of all trial types, indicating that the cues were successful in heightening attention at their location. The crucial point came in the comparison of the 2 invalid trial types. Despite being the same distance away from the cue and subject to the same variations of orientation, the within-object invalid trials were responded to faster than the different-object invalid trials. This suggests that an advantage was conferred upon the invalid-within object trials simply due to the presence of a shape containing both cue and target locations. This has been described as “Object Based Attention” – that attending to a cue within an object will heighten attention deployment to the whole object, including non-cued locations. More recently Luo, Lupianez, Funes, & Fu (2011) replicated these findings, and found that these object-based effects could be expected to be present even at very short stimulus onset asynchronies. They also highlighted problems in using cues and targets which contain implicit spatial information - something which was deliberately avoided in this study. Li & Logan (2008) sought to explore how object based attention relates to reading. They performed an almost direct replication of Egly et al. (1994), but replaced the shapes with 2-character Chinese words. The words could be oriented either horizontally or vertically in their experiment, following the rules in the Chinese writing system. The study was a target detection task with three conditions of cue-target relationship. The cues could be valid, invalid but within the same word, and invalid and located in a different word. Replicating Egly et al. (1994), Li and Logan (2008) found that valid trials were responded to fastest. Comparing the invalid trials it was found that invalid targets occurring within the same word as the cue were responded to faster than invalid targets occurring within a different word from the cue. This successful replication of Egly et al. (1994) and may be taken as evidence that words are treated like objects inasmuch that cues falling within a word measurably facilitate target detection