APES

Software:

APES icon APES - The Affective Picture Evaluation System, presents standard NIMH images (IAPS) and/or stimuli to human subjects and records conditioned and unconditioned responses.

The researcher initially sets up a PARAMETER file, specifying the stimuli to be applied, the data to be collected and the images to be presented for each trial of a run. Images are maintained in a database and can be reviewed and collected into "slide shows".

At the start of the run of trials for a particular subject, Subject and session ID information are entered.

Each trial is composed of several intevals, the duration of which the researcher specifies in the Parameter file. Pre stimulus or baseline interval, Post stimulus and/or Image display interval, Settling interval, Subjective response input interval, Inter-trial delay interval.

During the course of the trial, the subject is presented with visual and voice instructions such as: "Please sit still, baseline being collected", "Look at the large screen", "Enter how you feel on the touch screen", "Please relax", etc. Visual messages displayed on the video screen, and Voice messages need not be in English as the researcher may record whatever messages he pleases for each interval of the trial.

Up to 8 stimuli may be applied during the trial. Stimuli may be randomly applied for certain trials, and certain stimuli may be linked to one another.

Up to 8 autonomic responses such as: heart rate, skin conductance, eyeblink, EKG, EMG etc. may be collected continuously during the trial.

Data is stored in a separate data file for each run of trials. The PARAMETERS and STIMULI used during the run are stored with the collected data. The data may be graphically reviewed, trial by trial. Here eyeblink data (Clock #1) during trial 1 for subject ANDREA is displayed. Written reports compile stats on responses during all trials of a run. Summarized output files are created for export to other data analysis programs such as SASS.

Hardware:

Three VGA compatible video monitors are used on a Windows 98 computer. Two are used by the subject, the third, separate video monitor, is used by the researcher to monitor and control the experiment. It displays current status, responses, image being presented to the subject and a preview of the image to be presented in the next trial.

One video monitor (typically large screen) presents the affective image to the subject.

One video monitor with a touch senstive screen is used to collect subject input on their subjective reactions to the image. Up to 4 subjective inputs (valance, control, arousal, etc.) may be collected by the researcher.