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Experimental Protocol

In this experiment, a single subject intentionally expressed eight affective states toward a computer over a period of 32 days. Each affect state was maintained for an average of three minutes. A total of twenty usable days of data were collected due to sensor failure during some days. Data from four sensors, a skin conductance sensor, a photoplethysmeograph, a respiration sensor and an electromyogram (EMG), was collected and sampled at 20 samples per second using the ProComp unit from Thought Technologies, Ltd.

The subject, an actress trained in guided imagery techniques, was asked to experience and intentionally express eight affective states using a computer controlled prompting system developed by Manfred Clynes for the Sentic Cycles experiment. This experiment was chosen for ease of use and because Clynes reported finding a unique finger pressure signature for each of the eight emotion states used [4]. These states: no emotion, anger, hate, grief, love, romantic love, joy and reverence, are not the most commonly used in human computer design research, but they provide a set of affective states which span the ranges of high and low arousal and positive and negative valence.

Descriptive guidelines on the meaning of each emotion word were given to the subject before the experiment. The subject then reported the images she used to induce each state and the degree to which she found each experience arousing (exciting, distressing, disturbing, tranquil) and the degree to which they felt the emotion was positive or negative (valence). Daily ratings varied in intensity, but the overall character of each state was consistent, as described in Table 1.


 
Table: A description of the emotional states intentionally induced and expressed in this experiment

Emotion

Imagery Description Ar. Val.

no

blank paper boredom low neut.
emotion typewriter vacancy    
anger people who desire very very
  aroused anger to fight high neg.
hate injustice passive low neg.
  cruelty anger    
grief deformed child loss high neg.
  loss of mother sadness    
love family happiness low pos..
  summer peace    
r. love romantic excitement very pos.
  encounters lust high  
joy Ode uplifting med. pos.
  to Joy happiness high  
rev- church calm very neut.
erence prayer peace low  

       
 


next up previous
Next: Feature Extraction Up: Digital Processing of Affective Previous: Introduction
Jennifer Healey - fenn@media.mit.edu
1999-02-11