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                           FIFTH AMENDED AND RESTATED
                            ARTICLES OF INCORPORATION

                                       OF
                         BIOMAGNETIC TECHNOLOGIES, INC.

                            a California corporation

                                    ARTICLE I

                  The name of the corporation is 4-D Neuroimaging.

                                   ARTICLE II

                  The purpose of the corporation is to engage in any lawful act
or activity for which a corporation may be organized under the General
Corporation Law of California other than the banking business, the trust company
business or the practice of a profession permitted to be incorporated by the
California Corporations Code.

                                   ARTICLE III

                  The corporation elects to be governed by all the provisions of
the General Corporation Law (as added to the California Corporations Code
effective January 1, 1977, and as subsequently amended) not otherwise applicable
to this corporation under Chapter 23 of said General Corporation Law.

                                   ARTICLE IV

                  The corporation is authorized to issue one (1) class of stock
to be designated "Common Stock." The total number of shares which the
corporation is authorized to issue is Two Hundred Million (200,000,000) shares,
of which all such shares shall be Common Stock, without par value.
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                                    ARTICLE V

                  SECTION 1. The liability of the directors of the corporation
         for monetary damages shall be eliminated to the fullest extent
         permissible under California law.

                  SECTION 2. This corporation is authorized to indemnify the
         directors and officers of this corporation to the fullest extent
         permissible under California law.

                  SECTION 3. The corporation is authorized to provide
         indemnification of agents (as defined in Section 317 of the California
         Corporations Code) through bylaw provisions, agreements with agents,
         vote of shareholders or disinterested directors or otherwise, in excess
         of the indemnification otherwise permitted by Section 317 of the
         California Corporations Code, subject only to the applicable limits set
         forth in Section 204 of the California Corporations Code with respect
         to actions for breach of duty to the corporation and its shareholders.

         3. The foregoing amendment and restatement of the Articles of
Incorporation has been duly approved by the board of directors.

         4. The foregoing amendment of the Articles of Incorporation has been
duly approved by the holders of the requisite number of shares of said
corporation in accordance with California Corporations Code Sections 902 and
903. The total number of outstanding shares entitled to vote with respect to the
foregoing amendment was 83,403,112 shares of Common Stock. The number of shares
voting in favor of the foregoing amendment equaled or exceeded the vote
required, such required vote being a majority of the outstanding shares of
Common Stock.

         We declare under penalty of perjury under the laws of the State of
California that the matters set forth in this Certificate are true and correct
as of our own knowledge.

         Executed this 27 day of March, 2000, at San Diego, California.


                                    /s/ D. Scott Buchanan
                                    ----------------------------------
                                    D. Scott Buchanan
                                    President

                                    /s/ Aron P. Stern
                                    ----------------------------------
                                    Aron P. Stern
                                    Secretary