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Michael A. Lawrence added e2_methods.tex
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\subsection{Methods}
\subsubsection{Design}
The experiment employed a endogenous cuing paradigm whereby a central cue stimulus imperfectly predicted the location of a subsequent target stimulus. As in Experiment 1, participants were required to indicate detection of the target stimulus as rapidly as possible, followed by unspeeded report of the target color. On 1/6 of trials, the cue provided no spatial prediction (``neutral cue''); within the trials on which the cue provided spatial prediction, the cue was valid 80\% of the time and invalid 20\% of the time. Targets could appear on the left or right side of the screen and on 20\% of trials no target was presented, serving as catch trials to discourage anticipatory responding. Thus, 6$\times$2$\times$5 = 60 trials are necessary to complete the design. A total of 420 trials were presented to participants across 7 blocks, where order of trials was randomized within each block of 60 trials and participants were provided opportunity to take a break every 30 trials. Participants also completed 30 practice trials sampled randomly from the 60 trials of the complete design. The cue stimuli, described in the materials section to follow, were numeric in nature and thus may exert automatic spatial orienting via the SNARC effect \citep{Fischer2003,Dehaene1993}. To control for and examine this, two groups of participants were created: those for which the cue-space mapping was compatible with the SNARC effect (low numbers cuing left space) and those for which the cue-space mapping was incompatible with the SNARC effect (low numbers cuing right space). Participants were assigned to these groups alternately in order of participation.
\subsubsection{Participants}
Participants were recruited from a local undergraduate participant pool and included a total of 80 individuals. However, due to variability in the time participants took to complete each trial, 9 participants failed to complete the entire experiment within the allotted time and were consequently removed from analysis. A further 3 participants were observed to have considerably outlying performance on the color wheel task, both in terms of absolute error and in terms of estimated probability and fidelity of memory, and were consequently excluded. Thus, the data presented here consist of 68 participants (20 males, 7 left-handed, aged between 18 and 30).
\subsection{Materials}
Materials were the same as in Experiment 1 with the exception of the fixation and cue stimuli. The fixation stimulus was a central line rendering of the number ``8'', subtending a width of 0.375\degree and a height of 0.75\degree . Cue stimuli consisted of removal of either the upper-left and lower-right lines of the ``8'', rendering a ``2'', or the lower-left and upper-right lines of the ``8'', rendering a ``5'', or the upper and lower lines, rendering an ``H''.
\subsubsection{Procedure}
Following consent procedures, participants received verbal instructions describing the task (see Appendix B). For half the participants (SNARC compatible group) the endogenous cues, ``2'' and ``5'', were mapped to indicate target would likely appear on the left and right, respectively, for the other half of participants this mapping was reversed (SNARC incompatible group). All participants were instructed that if an ``H'' appears, the cue was equally likely to appear on the left or right. Each block started with the presentation of the fixation stimulus for 1s. A trial began with the onset of the three boxes, followed by the cue 1000ms later. After an SOA of 800ms the target appeared for 200ms. After response or response timeout after 1500ms, the screen was cleared and a color wheel and mouse cursor were presented on screen. Upon clicking an area of the color wheel, the screen was cleared, leaving only the fixation stimulus for 1000ms before the beginning of the next trial.
