Vertical versus horizontal Spatial-Numerical Associations (SNA): A processing advantage for the vertical dimension
Fig 1
Experimental setup as experienced by a participant.
As per the sketch on the right of the figure showing a view over a participant’s shoulder, participants used the joystick placed in front of them to indicate the corner of the screen the larger of the two numbers (the target) appeared in each trial. A representative sequence of theoretical screens is also shown across the top of the figure, with the number pair 6,8 shown on the screen, followed by a centrally located (+) for 500 ms, then another number pair, which in this example is 4,2. The repeating pattern of a number pair (trials to which the participant responded with the joystick), then central (+), before further number pair trials comprised the main experimental task. Inset on the lower left of the figure is an indicative drawing of a ball-top joystick, as used by participants to give their response. The joystick allowed for any movement direction along the device’s axial plane in two dimensions. Participants could hold the joystick in whatever grip style they felt was comfortable.