A processing division on the recency axis: The selective effects of visual field,match type,and direction of reading on terminal and pre-terminal items in a letter matching task

Four experiments were conducted to evaluate the hypothesis that different processes are involved in decisions about terminal and pre-terminal items in a sequential item recognition task. The impetus for the investigation was previous findings that the matching of terminal and pre-terminal items to simultaneously presented bilateral probes yielded a right visual field (RVF) and left visual field (LVF) advantage respectively.Experiments 1 and 2 demonstrated that the interaction between match type and visual field, generally attributed to hemispheric specialization, is restricted to decisions about terminal items, while the left visual field advantage found for pre-terminal items was dependent on a left-to-right scanning strategy. Experiments 3 and 4 provided further evidence that a serial search through the probe set determined responses to pre-terminal items by showing that the effect was dependent on a varied mapping between stimuli and targets. When target items could be identified without a serial search through the memory set, the left visual field advantage for pre-terminal items was abolished.The results confirm that distinct processing principles are involved in decisions about terminal and pre-terminal items in recognition memory. They suggest that the process responsible for decisions about pre-terminal items involves a habit-controlled scanning mechanism operating serially on spatially distributed information. The process responsible for decisions about terminal items may be based on either: (a) hemispheric principles, or (b) a link between the content of attention and spatially distributed expectations.