Human Research Protection Program at Purdue
Online Experiments
History of EE595T/PSY594I Psychophysics
Prof. Tan (ECE) and
Prof. Pizlo (PSY)
had independently
come up with the idea of a course on Psychophysics.
When the two of us realized that we both had an interest in developing
such a course, we decided to join force.
While many people view Psychophysics as nothing more than
a collection of methods
for performing experiments (limits, adjustment, constant stimuli etc.),
we developed our course with a broader view.
Our syllabus covers the methodology
of studying the relation between geometrical and physical properties of
objects and the percept. By studying it is meant not only collecting
data, but also formulating mathematical and computational models of the
underlying mental mechanisms. Traditionally, psychophysics is included as
an introductory part of courses on perception. This is usually limited to
a brief review of classical methods described by Fechner, and selected
methods that were developed in the 20th century (signal detection with the
receiver operating characteristic, speed-accuracy tradeoff, attention
operating characteristic, information transfer, adaptive methods). Such
an introduction is usually limited to 2 or 3 weeks, so that there is
enough time for discussing results and theories of perception. We
realized that a comprehensive review of all important experimental
methods, as well as review of mathematical and computational tools used in
modeling perceptual mechanisms (not to mention demos illustrating the use
of the experimental methods and data analysis) calls for a full semester
course.
Both of us have educational and research experience in both engineering
and psychophysics. Prof. Tan was trained in Electrical Engineering and
Computer Science, but has conducted extensive psychophysical experiments
on haptic perception. Prof. Pizlo has doctoral degrees in
Electronics as well as in Psychology.
We feel strongly that psychophysics has been, and
continues to be, a multidisciplinary endeavor. In the 19th century,
people such as Fechner, Weber, Helmholtz, Hering, Maxwell, and
Wundt were active in using and perfecting psychophysics
(both experimental methods and
mathematical models). In the 20th century, the development in a number of
engineering areas such as machine vision and image analysis started
attracting engineers to the field of psychophysics. It follows that
this course has been
designed to meet the needs of a wide range of groups (psychologists,
biologists, physicists, engineers), and to facilitate the interaction among
those groups.
Prof. Pizlo had previously used
web-based demonstrations in his course on
Perception (PSY628).
It was thought that similar demonstrations of psychophysical paradigms
would greatly facilitate student's learning.
Towards that goal, this website was setup during the Spring of 2000.
Initial demos were closely based on those used in PSY628.
As time went on, other demos (such as those for detection theory) were
added to this site.
The first offering of this course, called "Psychophsyics for Interface
Engineering," occurred during the Fall of 2000. Profs. Tan and Pizlo taught
the course together. A total of thirteen Purdue graduate students from
Engineering and Psychology majors took the course. Lectures were held
in a state-of-the-art classroom (MSEE184)
where each student had access to an HP
workstation. During the lectures, students would spent 10-15 minutes
to run demo experiments on themselves. Their results were then collected
and discussed immediately afterwards. Many students commented that the
on-line demos gave them
hands-on experience with experimental methods that greatly facilitated
grasping the underlying theoretical and practical aspects of psychophysics.
On August 7, 2001, Profs. Tan and Pizlo jointly presented a one-day
tutorial on Psychophysics at
The 9th International Conference on Human Computer Interaction
(HCII 2001). We presented it again as a half-day tutorial on June 23, 2003
at HCI International 2003, and as a one-day tutorial on July
24, 2005 at HCI International 2005.
Prof. Tan taught a half-day tutorial to Mechatronics students
at Gwangju Institute of Science and Technology in South Korea on
July 21, 2009.
Most recently, Prof. Tan co-presented a half-day tutorial with
Dr. Lynette Jones (MIT) at the World Haptics Conference 2011
on June 21, 2011.
The course was offered in Fall 2001 and Fall 2002 under the new
name Psychophysics. Since Fall 2005, it has been permanently
cross-listed in the School of Electrical and Computer Engineering and the
Department of Psychological Sciences as ECE511/PSY511 Psychophysics.
Acknowledgment
Many individuals have contributed to this website. Seungmoon Choi set up
this website in Spring 2000 and developed many demos used during the first
offering of this course. He received much help
from Prof. Greg Francis (PSY) and Mike Scheessele. Pamela Wilson
made improvements to the existing JAVA-codes in Fall 2000.
Filip Pizlo, Brian House, and Matthew Pearson are continuing to polish
up exiting demos and creating new ones for this website.
This website has been partly supported by a National Science
Foundation Faculty Early Career Development (CAREER) Award under
Grant No. 9984991-IIS.
Disclaimer
It is the intention of Profs. Tan and Pizlo to use the demos available
on this website for teaching Psychophysics. These demos are
not meant to be "perfect" examples of how a particular experiment
should be conducted. Instead, they are used to familiarize students
with the procedures of many experimental paradigms, and to expose
students to issues and problems related to the design of
psychophysical experiments. The instructors and students have enjoyed
and learned much from discussions on how these online demos can be improved.