EXHIBIT 10.1

4-D NEUROIMAGING        COMMON STOCK PURCHASE AGREEMENT        December 16, 2002

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TABLE OF CONTENTS

|   |  |                                                    |  |                                               |  | Page
|-- |  | -------------------------------------------------- |  | --------------------------------------------- |  | ----
|1. |  | Purchase and Sale of Stock                         |  | 1                                            
|   |  | 1.1                                                |  | Sale and Issuance of Common Stock             |  | 1   
|   |  | 1.2                                                |  | Closing                                       |  | 1   
|   |  | 1.3                                                |  | Subsequent Closings.                          |  | 1   
|2. |  | Representations and Warranties of the Company      |  | 1                                            
|   |  | 2.1                                                |  | Organization, Good Standing and Qualification |  | 1   
|   |  | 2.2                                                |  | Capitalization                                |  | 1   
|   |  | 2.3                                                |  | Authorization                                 |  | 1   
|   |  | 2.4                                                |  | Offering                                      |  | 2   
|   |  | 2.5                                                |  | Changes                                       |  | 2   
|   |  | 2.6                                                |  | Disclosure                                    |  | 2   
|   |  | 2.7                                                |  | Corporate Documents                           |  | 2   
|3. |  | Representations and Warranties of the Investors    |  | 2                                            
|   |  | 3.1                                                |  | Authorization                                 |  | 2   
|   |  | 3.2                                                |  | Purchase Entirely for Own Account             |  | 2   
|   |  | 3.3                                                |  | Disclosure of Information                     |  | 2   
|   |  | 3.4                                                |  | Investment Experience                         |  | 2   
|   |  | 3.5                                                |  | Accredited Investor                           |  | 3   
|   |  | 3.6                                                |  | Restricted Securities                         |  | 3   
|   |  | 3.7                                                |  | Further Limitations on Disposition            |  | 3   
|   |  | 3.8                                                |  | Legends                                       |  | 3   
|   |  | 3.9                                                |  | Further Representations by Foreign Investors  |  | 4   
|   |  | 3.10                                               |  | Tax Advisors                                  |  | 4   
|   |  | 3.11                                               |  | Investor Counsel                              |  | 4   
|4. |  | California Commissioner of Corporations            |  | 4                                            
|   |  | 4.1                                                |  | Corporate Securities Law                      |  | 4   
|5. |  | Conditions of the Company's Obligations at Closing |  | 4                                            
|   |  | 5.1                                                |  | Representations and Warranties                |  | 4   
|   |  | 5.2                                                |  | Payment of Purchase Price                     |  | 4   
|   |  | 5.3                                                |  | Qualifications                                |  | 4   
|6. |  | Miscellaneous                                      |  | 5                                            
|   |  | 6.1                                                |  | Survival                                      |  | 5   
|   |  | 6.2                                                |  | Successors and Assigns                        |  | 5   
|   |  | 6.3                                                |  | Governing Law                                 |  | 5   
|   |  | 6.4                                                |  | Titles and Subtitles                          |  | 5   
|   |  | 6.5                                                |  | Notices                                       |  | 5   
|   |  | 6.6                                                |  | Finder's Fee                                  |  | 5   
|   |  | 6.7                                                |  | Expenses                                      |  | 5   
|   |  | 6.8                                                |  | Severability                                  |  | 5   
|   |  | 6.9                                                |  | Entire Agreement                              |  | 5   
|   |  | 6.10                                               |  | Counterparts                                  |  | 5   

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COMMON STOCK PURCHASE AGREEMENT

THIS COMMON STOCK PURCHASE AGREEMENT (this "Agreement") is entered into effective as of December 16, 2002, by 4-D Neuroimaging, a California
corporation (the "Company"), and the investor(s) listed on Schedule A (each, an "Investor" and collectively, the "Investors"). THE PARTIES HEREBY AGREE AS FOLLOWS:

1.Purchase and Sale of Stock.



2.Representations and Warranties of the Company.The Company hereby represents and warrants to each Investor
that, as of the date hereof except as otherwise provided below:



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3.Representations and Warranties of the Investors.Each Investor hereby represents, warrants and covenants
that:



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4.California Commissioner of Corporations.



5.Conditions of the Company's Obligations at Closing.The obligations of the Company to each Investor under
this Agreement are subject to the fulfillment on or before the Closing of each of the following conditions by that Investor:



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6.Miscellaneous.



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IN
WITNESS WHEREOF, the parties have executed this Agreement as of the date first above written.

| |  |          |  | 4-D NEUROIMAGING, a California corporation                                               
| |  | -------- |  | -----------------------------------------------------------------------------------------
| |  |          |  | By:                                                                                      
| |  |          |  |                                                                                          
| |  | Address: |  | 9727 Pacific Heights Blvd.,
San Diego, California, USA 92121
Facsimile No. (858) 458-5698
| |  |          |  | INVESTOR:                                                                                
| |  |          |  |                                                                                          
| |  |          |  | By:                                                                                      
| |  |          |  |                                                                                          
| |  | Address: |  |                                                                                          
| |  |          |  |                                                                                          
| |  |          |  | Facsimile No.                                                                            
| |  |          |  |                                                                                          
| |  |          |  | E-mail:                                                                                  
| |  |          |  |                                                                                          

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SCHEDULE A

SCHEDULE OF INVESTORS

|Investors |  | Number of Shares |  | Purchase Price
|--------- |  | ---------------- |  | --------------
|INVESTOR  |  |                  |  |               

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