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                                                                    Exhibit 10.2


                                 LOAN AGREEMENT


This agreement dated June 28, 2000, is by and between 4-D Neuroimaging, a
California corporation based in San Diego, CA (the "Borrower"), and BDN, a
company based in Madrid, Spain (the "Lender"), (each the "Party" and together
the "Parties").

WHEREAS, the Borrower has the necessity to borrow funds from the Lender to pay
the interest due to AIG Private Bank, Limited, and

WHEREAS, the Lender is able to and agrees to provide funds sufficient for the
purpose intended, and

NOW, THEREFORE, Lender hereby agrees to provide to Borrower a loan for such
purposes. This loan is made available to the Borrower by the Lender based on the
following terms, conditions and procedures:

FORM OF LOAN:                       This loan takes the form of a Promissory
                                    Note, which accrues simple interest and can
                                    be repaid in part or in whole at any time.

TERM, DURATION:                     This loan shall be made available to
                                    Borrower for a period beginning the date
                                    indicated above, and ending on September 30,
                                    2000. All amounts owed shall become due and
                                    payable on this date, unless otherwise
                                    amended in writing by mutual agreement.

ACKNOWLEDGEMENT:                    The loan is authenticated by the signing of
                                    this document below, by duly authorized
                                    representatives of the respective Parties.

AMOUNT, PURPOSE AND                 The amount of this loan is $484,595.26 and
FUNDS TRANSFER:                     is to be used for the payment of interest
                                    owed to AIG Private Bank, Ltd., loan
                                    agreement #249-8380.

                                    The Lender shall transfer funds directly to
                                    AIG Private Bank, Ltd., Zurich, attention
                                    Esther Gauch. She can be reached at:

                                        Tel. +41 (1) 824 64 44
                                        Fax  +41 (1) 824 64 50
                                        Email e.gauch@aipb.com


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Loan Agreement                                                            Page 2


INTEREST RATE AND                   The interest rate shall be based on the
PAYMENT:                            three month U.S dollar LIBOR + 1%, rounded
                                    up to the nearest quarter percent in USD.
                                    The U.S. dollar LIBOR rate shall be
                                    determined by referring to the quoted rate
                                    in the Wall Street Journal printed on the
                                    date indicated above, representing the prior
                                    day's three month rate. The rate shall
                                    continue effective until September 30, 2000.

INTEREST ACCRUAL:                   Interest shall accrue during the period and
                                    shall not compound, commencing with the day
                                    of receipt of the funds. Interest shall be
                                    calculated daily and accrued monthly if not
                                    paid. At the end of the period all principal
                                    and interest shall become due and payable.
                                    If interest is not paid then compounding
                                    will commence.

CURRENCY EXCHANGE:                  Borrower shall be held responsible for
                                    paying the interest and repaying the
                                    principal in the Lender's currency.

REPAYMENT:                          The Borrower can repay in part or in whole
                                    all outstanding amounts owed, including
                                    interest, at any time, all interest due
                                    being paid first, then principal, without
                                    penalty, to the bank indicated by Lender.

PLEDGES:                            Working capital assets such as receivables
                                    may be pledged as security for the loan upon
                                    mutual agreement, but are not a necessary
                                    precondition for funds to be drawn down.

ASSIGNABILITY:                      The Lender retains the right to assign this
                                    Loan Agreement to any party without
                                    modification, or if modifications are
                                    required, by receiving in advance the
                                    written consent of the Borrower.


This Loan Agreement has been executed by the Persons below as of the date
indicated above, each Person being the duly authorized representative.


/s/ Felipe Fernandez                      /s/ D. Scott Buchanan
-----------------------------------       --------------------------------------
Mr. Felipe Fernandez                      Dr. D. Scott Buchanan
BDN Spain                                 4-D Neuroimaging
Lender                                    Borrower