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                                                                    Exhibit 10.1

[Fleet Logo]  FLEET

                       SECOND AMENDMENT TO LOAN AGREEMENT



         THIS AMENDMENT is made as of May 9, 2002 by ASPECT MEDICAL SYSTEMS,
INC. (the "BORROWER") and FLEET NATIONAL BANK (the "LENDER").

                                    RECITALS

         A. The Lender and the Borrower are parties to a letter agreement dated
as of May 16, 2001, as amended by that certain First Amendment to Loan Agreement
dated as of December 21, 2001 (as the same has been and may hereafter be
amended, supplemented or otherwise modified from time to time, the "LOAN
AGREEMENT"). Capitalized terms used herein without definition have the meanings
assigned to them in the Loan Agreement.

         B. The Borrower and the Bank desire to extend the maturity date of the
Revolving  Loans and modify certain of the financial covenants contained in the
Loan Agreement.

         NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties hereto agree as
follows:

I.       AMENDMENTS TO LOAN AGREEMENT.

         A. Section 3.7 of the Loan Agreement is hereby deleted in its entirety
and replaced with the following:

         "3.7. MINIMUM READY ASSET BALANCE. The Borrower will maintain at all
         times an aggregate amount of Ready Assets with a net equity value
         (determined at face value) in excess of $20,000,000."

         B. Section 3.8 of the Loan Agreement is hereby deleted in its entirety
and replaced with the following:

         "3.8 MINIMUM TANGIBLE NET WORTH. The Borrower will maintain, at all
         times, a Tangible Net Worth in excess of $30,000,000."

         C. The definition of "Expiration Date" contained in Section 7.1 of the
Loan Agreement is hereby deleted in its entirety and replaced with the
following:

         "'Expiration Date' - May 14, 2003, unless extended by the Bank which
         extension may be given or withheld by the Bank in its sole discretion."


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II.      NO FURTHER AMENDMENTS.

         Except as specifically amended hereby, the Loan Agreement and the
Pledge Agreement shall remain unmodified and in full force and effect and are
hereby ratified and affirmed in all respects, and the indebtedness of the
Borrower to the Lender evidenced thereby and by the Revolving Note is hereby
reaffirmed in all respects. On and after the date hereof, each reference in the
Loan Agreement to "this letter agreement", "hereunder", "hereof", or words of
like import referring to the Loan Agreement, shall mean and be a reference to
the Loan Agreement as amended by this Amendment, and each reference in Pledge
Agreement to the Loan Agreement, "thereunder", "thereof", or words of like
import referring to the Loan Agreement shall mean a reference to the Loan
Agreement as amended by this Amendment.

III.     CONFIRMATION OF SECURITY.

         The Pledge Agreement shall remain in full force and effect and is
hereby ratified and affirmed in all material respects. The Borrower hereby
acknowledges and agrees that the "Obligations" secured by and entitled to the
benefits of the Pledge Agreement include, without limitation, the Revolving
Note.

IV.      MISCELLANEOUS.

         A. As provided in the Loan Agreement, the Borrower agrees to reimburse
the Lender upon demand for all out-of-pocket costs, charges, liabilities, taxes
and expenses of the Lender (including reasonable fees and disbursements of
counsel to the Lender) in connection with the (a) preparation, negotiation,
interpretation, execution and deliver of this Amendment and any other
agreements, instruments and documents executed pursuant or relating hereto, and
(b) any enforcement hereof.

         B. This Amendment shall be governed by and construed in accordance with
the laws of the Commonwealth of Massachusetts.

         C. This Amendment may be executed by the parties hereto in several
counterparts hereof and by the different parties hereto on separate counterparts
hereof, all of which counterparts shall together constitute one and the same
agreement. Delivery of an executed signature page of this Amendment by facsimile
transmission shall be effective as delivery of a manually executed counterpart
hereof.



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IN WITNESS WHEREOF, the Lender and the Borrower have caused this Amendment to be
duly executed as a sealed instrument by their duly authorized representatives,
all as of the day and year first above written.


                                          ASPECT MEDICAL SYSTEMS, INC.

                                          By: /s/ J. Neal Armstrong
                                              ----------------------------------
                                              Name:  J. Neal Armstrong
                                              Title:  Vice President and CFO


                                          FLEET NATIONAL BANK

                                          By: /s/ T. Clark Hayes
                                              ----------------------------------
                                              Name:  T. Clark Hayes
                                              Title:  AVP