Figure 1
From: Bringing the real world into the fMRI scanner: Repetition effects for pictures versus real objects
Experimental setup, stimulus items and fMRI trial sequence.
(a) Participants lay supine in the MR scanner with the head supported within the lower portion (6 elements) of an inclined 12-channel head coil. A 4-channel flex coil was positioned over the front of the head. The head coil was tilted forward by ∼30o to enable direct viewing of stimuli. 2D pictures and 3D object stimuli (illustrated above) were mounted by the experimenter on a turntable positioned over the waist. The experiment was conducted in complete darkness and all trials recorded using an infra-red camera. Stimulus presentation duration was controlled by an LED (illuminator). Participants were asked to identify the objects presented on each trial while maintaining fixation on a single red LED positioned just above the stimulus plane. (b) Six sets of 5 stimulus exemplar objects were used in the fMRI-A experiment (30 in total). A different set of stimulus items was used in each run to prevent cross-adaptation. 3D stimuli from ‘Set 1’ are depicted in (a) and (c). (c) Example trial sequence. Each stimulus item was presented for 500ms within a 3 sec inter-stimulus interval. Stimuli for each upcoming trial were positioned on the turntable during the 20 sec inter-trial interval.
