AMENDMENT AGREEMENT

                               AMENDMENT AGREEMENT

This Amendment Agreement ("Amendment") is entered into as of May 25, 2000 by
and between BioSignal Inc. 0000 xxx Xxxxxxx, Xxxxxxxx, Xxxxxx XXXXXX X0X 0X0
(hereinafter, BIOSIGNAL) and Vanderbilt University, through the Office of
Technology Transfer, having an office at 0000 00xx Xxxxxx X. Xxxxx 000,
Xxxxxxxxx XX XXX 00000 (hereinafter, VANDERBILT).

   WHEREAS, BIOSIGNAL and VANDERBILT entered into a License Agreement relating
   to: "Optical Assay of Protein Interactions" as of September 11, 1998
   (AGREEMENT), and

   WHEREAS, BIOSIGNAL and VANDERBILT wish to amend the AGREEMENT,

   NOW, THEREFORE, BIOSIGNAL and VANDERBILT agree as follows:

The AGREEMENT is hereby amended effective as of the date first written above as
follows:

   Section 3 CONSIDERATIONS & ROYALTIES is amended by inserting a new Clause
   3.8, to read as follows:

   "For sales of a LICENSED SERVICE in combination with other products and/or
   services ("COMBINATION SERVICE") the earned royalty shall be [* * *] of the
   NET SALES of the COMBINATION SERVICE that could not have been performed but
   for the INVENTION."

IN WITNESS WHEREOF, the parties hereto have set their hands and seals and duly
executed this AGREEMENT on the dates indicated below, to be effective on the
date first written above.

BioSignal Inc.                                  Vanderbilt University

By:  /s/ Xxxxxx Xxxxxxx                         By: /s/ Xxxxx Xxxxxx
     --------------------------                     ----------------------------
     Xxxxxx Xxxxxxx, Ph.D.                          Xxxxx Xxxxxx
     President                                      Assoc. Director


[* * *] Indicates information omitted pursuant to a request for confidential
treatment and filed separately with the Securities and Exchange Commission
pursuant to Rule 24b-2 under the Securities Exchange Act of 1934,
as amended.