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                                  EXHIBIT 10.1


                AGREEMENT BETWEEN 4-D AND AIG PRIVATE BANK LTD.,

                       DATED ON OR ABOUT FEBRUARY 15, 2001





                    (This agreement has been superceded by the
                            agreement in Exhibit 10.2)


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                                                                    EXHIBIT 10.1

                                       AIG
                                  ------------
                                  PRIVATE BANK


4-D Neuroimaging, Inc.
Attn: Mr. Scott Buchanan, CEO
9727 Pacific Heights Blvd.
San Diego,  CA  92121-3719
USA

Zurich, February 15, 2001

LOAN AGREEMENT NR 2498380


Dear Sirs,

With reference to our various discussions, we are pleased to prolongate the
increased loan facility to you on the following terms and conditions
(hereinafter referred to as the "Agreement"):

BORROWER

4-D Neuroimaging, Inc. 9727 Pacific Heights Blvd., San Diego,
CA 92121-3719, USA, formerly known as Biomagnetic Technologies, Inc.
(hereinafter referred to as the "Borrower")


LENDER

AIG Private Bank Ltd., Pelikanstrasse 37, P.O. Box 1376, CH-8021 Zurich
(hereinafter referred to as the "Lender")


LOAN AMOUNT

USD 11,951,000 (United States Dollars eleven million nine hundred and fifty one
thousand)


PURPOSE

Prolongation and increase of the existing credit line.


UTILISATION

In the form of a fixed term advance of USD 11,951,000.

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TERM / DURATION

This credit facility will be available until July 20, 2001 (the "Final Maturity
Date").


REPAYMENT

The Borrower shall repay in full the outstanding advance and interest made to it
on the Final Maturity Date.


INTEREST RATE

The Borrower agrees to pay interest on the outstanding principal amount in
accordance with the following provisions:

The interest rate for the fixed advance is based on our refinancing costs in
line with the current market conditions plus a fixed margin of 3.5% p.a.

Interest will be calculated on the basis of the exact number of days elapsed,
divided by a 360-day year (365/360) and will be payable on July 20, 2001.

If any sum due and payable by the Borrower is not paid when due, the interest on
any such amounts will be calculated on the basis of the refinancing costs of the
Lender, together with the margin of 5% (five per cent) per annum, for the period
beginning with the due date until receipt by the Lender of the payment.

If any payment date shall fall on a day on which banks in Zurich or New York are
not open for business, such payment date shall be extended to the next
succeeding business day unless such business day falls in the next calendar
month in which event such due date shall be the immediately preceeding business
day.


SECURITY

(a)  Pledge and assignment by Scaloway Co. Ltd. (hereinafter referred to as
     ("Guarantor").

(b)  Guarantee in the amount of USD 1,550,000 issued by Bank Julius Baer & Co.
     AG, Zurich as well as pledge and assignment form regarding 1832 shares of
     Neuromag Oy, Helsinki.


COSTS, FEES AND EXPENSES

The Borrower shall pay to the Lender on demand an amount equal to all costs,
charges and expenses (including, but not limited to, legal expenses and stamp
registration or other duties) incurred by the Lender in connection with
preparation and execution of this Agreement and the security and other
documentation contemplated hereby and all costs, charges and expenses (including
legal expenses on a full indemnity basis) of the Lender in connection with the
enforcement of or preservation of any of its rights under this Agreement or
otherwise in connection with the facility.


PAYMENTS AND TAXES

All payments to be made by the Borrower to the Lender under this Agreement shall
be made in United States Dollars, freely disposable outside of bilateral or
multilateral payment agreements which may exist at the time of payment, free and
clear of and without deduction of any taxes, levies, imposts, duties, charges,
fees, deductions or withholdings of any nature, now or hereafter imposed by or
on behalf of any taxing authority or any other entity.

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ASSIGNABILITY

The Lender has the right to assign this Agreement to any party without the
consent of the Borrower but it requires the consent of the Guarantor.


COVENANTS

The Borrower covenants that, until full and final payment of all indebtedness
and liabilities incurred hereunder, unless the Lender waives compliance in
writing, the Borrower will furnish the Lender with such information concerning
the affairs of the Borrower as the Lender may reasonably request.


EVENTS OF DEFAULT

The principal and accrued interest on any outstanding balances as well as any
and all accrued fees and charges whatsoever under this Agreement, shall become
immediately due and payable, without need of further legal formality, at the
option of and upon the first demand by the Lender, if:

a)   the Borrower shall default in the payment of principal or interest on any
     advance or of any other amount payable thereunder when the same shall
     become due and payable and such failure continues for a period of 5 (five)
     business days without remedy;
b)   the Borrower shall default in the performance of any term, covenant or
     condition contained in this agreement after written notice and failure to
     cure such default within thirty (30) days from the receipt of such notice
     or an event of default in the performance of any other agreement between
     the Borrower and the Lender;
c)   any representation or warranty made by the Borrower under this agreement or
     any certificate or documents furnished pursuant thereto, shall prove to
     have been untrue when made or at any subsequent time to be incorrect in any
     material respect;
d)   any other event occurs or circumstances arise which, in the opinion of the
     Lender is likely, materially and adversely, to affect the ability of the
     Borrower or any future mortgagor to perform all or any of his or its
     obligations under or otherwise to comply with the terms of this Agreement.

The Borrower shall hold the Lender harmless of and indemnify the Lender against
any losses or expenses which the Lender may sustain or incur as a consequence of
any Event of Default by the Borrower as stipulated herein.

If there is an Even of Default, the Lender reserves the right to increase the
interest rate and/or the commission rate, not to exceed twelve (12% p.a.)
percent per annum.


CONDITIONS PRECEDENT

This agreement its made under the condition and the Lender's obligation to make
this loan available is subject to the conditions precedent that the Lender shall
have received and approved the following:

a)   A signed copy of this agreement, each page initialed, bearing the
     authorized signature of the Borrower.

LAW GOVERNING THE LEGAL RELATIONSHIP BETWEEN THE LENDER AND THE BORROWER AND
PLACE OF JURISDICTION

All legal aspects of the relationship between the Borrower and the Lender shall
be governed by Swiss law. The place of performance, the exclusive place of
jurisdiction for lawsuits and all other kinds of legal proceedings and place of
foreclosure shall be the domicile of the Lender.

The Lender reserves the right to bring legal proceedings against the Borrower
before any competent court at the domicile of the Borrower or any other court
having jurisdiction over the Borrower.

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No failure to exercise and no delay in exercising on the part of the Lender any
of its rights hereunder shall operate as a waiver thereof, nor shall any single
or partial exercise or any rights preclude any other or further exercise
thereof.

The general pledge and assignment and our "General Banking Conditions" which you
already received, form an integral part of this loan agreement.

We hope that the above terms and conditions meet your requirements, and kindly
request that you duly sign and return to us the enclosed duplicates of this
agreement.

We remain,

Yours truly,

AIG Private Bank Ltd.

/s/ Daniel Sager                             /s/ Esther Gauch
------------------------------------------   -----------------------------------
Daniel Sager                                 Esther Gauch
Assistant Vice President Credit Department   Member of Management