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                                    COCENSYS, INC.                 EXHIBIT 10.1
                                EXECUTIVE OFFICERS'
                               SEVERANCE BENEFIT PLAN

SECTION 1.  INTRODUCTION.

     The CoCensys, Inc. Executive Officers' Severance Benefit Plan (the 
"Plan") was established effective March 26, 1998.  The purpose of the Plan is 
to provide for the payment of severance benefits to certain eligible 
employees of CoCensys, Inc. (the "Company") whose employment with the Company 
is involuntarily or constructively terminated.  This Plan shall supersede any 
severance benefit plan, policy or practice previously maintained by the 
Company. Notwithstanding the foregoing, this Plan shall not supersede the 
CoCensys, Inc. Executive Officers' Change of Control Severance Plan.  This 
Plan document is also the Summary Plan Description for the Plan.

SECTION 2.  ELIGIBILITY FOR BENEFITS.

     (a)  GENERAL RULES.  Subject to the requirements set forth in this 
Section, the Company will grant severance benefits under the Plan to Eligible 
Employees.  

          (i)  "ELIGIBLE EMPLOYEES" shall include the President, the Chief 
Executive Officer, any Vice President and the General Counsel of the Company. 
An Eligible Employee shall be entitled to the payment of severance benefits 
under the Plan in the event that such Eligible Employee's employment with the 
Company is involuntarily terminated without "Cause" (as defined below) or the 
Eligible Employee voluntarily leaves on account of a "Constructive 
Termination" (as defined below).  The Company shall make a reasonable good 
faith determination as to whether such an event has occurred; provided, 
however, that with respect to the Chief Executive Officer, such determination 
shall be made by a majority of the Board of Directors.  It shall be presumed 
that an Eligible Employee has not left the Company on account of a 
Constructive Termination if that Employee voluntarily leaves the Company more 
than sixty (60) days after the later of (A) the occurrence of an event giving 
rise to a claim of Constructive Termination or (B) receipt of notice of such 
event.

               (1)  As used herein "Cause" shall mean:  (A) an intentional 
act that materially injures the Company; (B) the intentional refusal or 
failure to follow the lawful and reasonable directions of the Board of 
Directors or the directions of any individual to whom the Eligible Employee 
reports; (C) the willful and habitual neglect of duties; or (D) the 
conviction of a felony involving moral turpitude which is reasonably likely 
to inflict or has inflicted material injury on the Company; PROVIDED that the 
Eligible Employee did not cure such misconduct within thirty (30) days 
following receipt of written notice of such misconduct from the Company.

               (2)  As used herein "Constructive Termination" shall mean:  
(A) the assignment of duties and responsibilities which result in a 
diminution of position or function (but not merely a change in title or 
reporting relationships); (B) the reduction in base salary by more than ten 
percent (10%); (C) a material reduction in the Eligible Employee's package of

                                       1.
<PAGE>

incentives and benefits in the aggregate; (D) the relocation of the Eligible 
Employee's principal office by more than thirty (30) miles, unless approved 
by the Eligible Employee; (E) the material breach of this Plan or any other 
material agreement between the Eligible Employee and the Company regarding 
the terms and conditions of employment; or (F) the failure of any acquiring 
or surviving corporation to assume the responsibilities of the Company under 
this Plan or under any other material agreement between the Eligible Employee 
and the Company regarding the terms and conditions of employment. 

          (ii)   In order to be eligible to receive benefits under the Plan, 
an Eligible Employee must remain on the job until his or her date of 
termination as scheduled by the Company.

          (iii)  In order to be eligible to receive benefits under the Plan, 
an Eligible Employee must execute a general waiver and release on a form 
provided by the Company.

     (b)  EXCEPTIONS.  An employee who otherwise is an Eligible Employee will 
not receive benefits under this Plan in any of the following circumstances:

          (i)   The employee has executed an individually negotiated 
employment contract or agreement with the Company relating to severance 
benefits that is in effect on his or her termination date.  Such employee's 
severance benefit, if any, shall be governed by the terms of such 
individually negotiated employment contract or agreement, subject to Section 
6(c) of this Plan.

          (ii)  The employee is involuntarily terminated for Cause.

          (iii) The employee voluntarily terminates employment with the 
Company not on account of a Constructive Termination.  Voluntary terminations 
include, but are not limited to, resignation, retirement, or failure to 
return from a leave of absence on the scheduled date, so long as such event 
is not on account of a Constructive Termination.

          (iv)  The employee voluntarily terminates employment with the 
Company in order to accept employment with another entity that is wholly or 
partly owned (directly or indirectly) by the Company or the parent or other 
affiliate of the Company.

          (v)   The employee has qualified to receive benefits under the 
CoCensys, Inc. Executive Officers' Change of Control Severance Plan.

SECTION 3.     AMOUNT OF BENEFIT.

     Severance benefits payable under the Plan are as follows:

     (a)  Eligible Employees whose employment is involuntarily terminated 
without Cause or is voluntarily terminated on account of a Constructive 
Termination as described in Section 2 of this Plan will receive the following 
benefits:

                                       2.
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          (i)  "Pay" (as defined below) for the number of months set forth 
below (the "Pay Continuation Period"):

<TABLE>
<CAPTION>
                                         Time with Company                 Pay
         Eligible Employee          (i.e., "vesting service")     Continuation Period
-----------------------------      --------------------------     --------------------
<S>                                <C>                            <C>
Chief Executive Officer/President      Less than 6 months                0 months
                                         6 to 12 months                  6 months
                                      more than 12 months               12 months

Vice President/General Counsel         Less than 6 months                0 months
                                         6 to 12 months                  3 months
                                      more than 12 months                6 months
</TABLE>

          (ii)  Payment of a "Target Bonus" (as defined below) pro rated for 
the actual period of employment (which does not include any of the Pay 
Continuation Period) with the Company during the year in which employment is 
terminated.

     (b)  For purposes of calculating Plan benefits:  (i) "Pay" shall mean 
the Eligible Employee's base pay (excluding overtime, bonuses, draws, 
commissions, and other forms of additional compensation), at the rate in 
effect during the last regularly scheduled payroll period immediately 
preceding the Eligible Employee's termination date and (ii) "Target Bonus" 
shall mean the Eligible Employee's target bonus for the year in which the 
Eligible Employee's employment with the Company is terminated without Cause 
or upon a Constructive Termination, in the amount approved by the 
Compensation Committee of the Board of Directors.

     (c)  Unless otherwise approved by the Board of Directors or an 
authorized Committee of the Board of Directors, the terms and conditions of 
any options to acquire Company stock, including without limitation the 
vesting, exercisability and termination of such options, held by the Eligible 
Employee on the termination date shall be determined solely in accordance 
with the Eligible Employee's stock option agreements and the Company stock 
option plans pursuant to which such stock options were granted. 

     (d)  Notwithstanding any other provision of this Plan to the contrary, 
any benefits payable to an Eligible Employee under this Plan shall be offset, 
to the maximum extent permitted by law, by any severance benefits payable by 
the Company to such individual under any other arrangement covering the 
individual.

SECTION 4.     TIME OF PAYMENT AND FORM OF BENEFIT.

     The Company reserves the right to determine whether the severance 
benefits under the Plan will be paid in a single sum or in installments and 
to choose the timing of such payments, provided, however, that all payments 
under this Plan will be completed within a period of time following an 
Eligible Employee's termination date not exceeding the Pay Continuation 
Period.  If a terminating employee is indebted to the Company at his or her 
termination date, the Company reserves the right to offset any severance 
payments under the Plan by the amount of
 
                                       3.
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such indebtedness.  In no event shall payment of any Plan benefit be made 
prior to the Eligible Employee's termination date.  

SECTION 5.  REEMPLOYMENT.

     Severance payments received under Section 3(a) of the Plan will cease in 
the event of an Eligible Employee's reemployment by the Company or any 
affiliate of the Company.

SECTION 6.  MISCELLANEOUS.

     (a)  EXCLUSIVE DISCRETION.  The Plan Administrator shall have the 
exclusive discretion and authority to establish rules, forms, and procedures 
for the administration of the Plan, and to construe and interpret the Plan 
and to decide any and all questions of fact, interpretation, definition, 
computation or administration arising in connection with the operation of the 
Plan, including, but not limited to, the eligibility to participate in the 
Plan and amount of benefits paid under the Plan.  The rules, interpretations, 
computations and other actions of the Plan Administrator shall be binding and 
conclusive on all persons.

     (b)  AMENDMENT OR TERMINATION.  The Company also reserves the right to 
amend or discontinue this Plan or the benefits provided hereunder at any 
time; provided, however, that no such amendment or termination shall affect 
the right to any unpaid benefit of any Eligible Employee whose termination 
date has occurred prior to amendment or termination of the Plan.  Any action 
amending or terminating the Plan shall be adopted by the Board of Directors 
of the Company or the Compensation Committee of the Board, and written notice 
of such amendment or termination shall be provided promptly to all Eligible 
Employees.

     (c)  OTHER SEVERANCE ARRANGEMENTS.  The Company reserves the right to 
make other arrangements regarding severance benefits in special 
circumstances.  The foregoing notwithstanding, in no event shall any 
individual receive from the Company any severance benefit greater than the 
benefit provided under Section 3, unless such individual executes, as a 
condition upon the receipt of such additional benefit, a waiver and release 
of any and all claims that such individual may have against the Company, on 
the form provided by the Company.

SECTION 7.  CONTINUATION OF EMPLOYMENT BENEFITS.

     (a)  COBRA CONTINUATION.  Each Eligible Employee who is enrolled in a 
health or dental plan sponsored by the Company may be eligible to continue 
coverage under such health or dental plan (or to convert to an individual 
policy), at the time of the Eligible Employee's termination of employment 
under the Consolidated Omnibus Budget Reconciliation Act of 1985 ("COBRA").  
The Company will notify the individual of any such right to continue health 
coverage at the time of termination.  The Company will continue to pay its 
share of the Eligible Employee's health insurance premiums during the Pay 
Continuation Period as long as the Eligible Employee elects to continue 
coverage under COBRA and timely pays the Eligible Employee's portion of the 
premiums. If and when the Eligible Employee becomes eligible for another 
group benefits plan through another employer, COBRA coverage through the 
Company will terminate (the "COBRA Period").  No provision of this Plan will 
affect the continuation

                                       4.
<PAGE>

coverage rules under COBRA, except that the Company's payment of any 
applicable insurance premiums during the COBRA Period will be credited as 
payment by the Eligible Employee for purposes of the Eligible Employee's 
payment required under COBRA.  Therefore, the period during which an Eligible 
Employee must elect to continue the Company's group medical or dental 
coverage at his or her own expense under COBRA, the length of time during 
which COBRA coverage will be made available to the Eligible Employee, and all 
other rights and obligations of the Eligible Employee under COBRA (except the 
obligation to pay insurance premiums that the Company pays during the COBRA 
Period) will be applied in the same manner that such rules would apply in the 
absence of this Plan. At the conclusion of the COBRA Period, the Eligible 
Employee will be responsible for the entire payment of premiums required 
under COBRA for the duration of the COBRA period.

     For purposes of this Section 7(a), applicable premiums that will be paid 
by the Company during the Pay Continuation Period shall not include any 
amounts payable by the Eligible Employee under the Company's Section 125 
health care reimbursement plan, which amounts, if any, are the sole 
responsibility of the Eligible Employee.

     (b)  OTHER EMPLOYEE BENEFITS.  All non-health benefits (such as life 
insurance and disability coverage) terminate as of the employee's termination 
date (except to the extent that any conversion privilege is available 
thereunder).

SECTION 8.  NO IMPLIED EMPLOYMENT CONTRACT.

     The Plan shall not be deemed (i) to give any employee or other person 
any right to be retained in the employ of the Company nor (ii) to interfere 
with the right of the Company to discharge any employee or other person at 
any time and for any reason, which right is hereby reserved.

SECTION 9.  LEGAL CONSTRUCTION.

     This Plan is intended to be governed by and shall be construed in 
accordance with the Employee Retirement Income Security Act of 1974 ("ERISA") 
and, to the extent not preempted by ERISA, the laws of the State of 
California.

SECTION 10. CLAIMS, INQUIRIES AND APPEALS.

     (a)  APPLICATIONS FOR BENEFITS AND INQUIRIES.  Any application for 
benefits, inquiries about the Plan or inquiries about present or future 
rights under the Plan must be submitted to the Plan Administrator in writing. 
 The Plan Administrator is:
                                          
                          Vice President, Human Resources
                                   CoCensys, Inc.
                                201 Technology Drive
                              Irvine, California 92618

                                       5.
<PAGE>
                                          
     (b)  DENIAL OF CLAIMS.  In the event that any application for benefits 
is denied in whole or in part, the Plan Administrator must notify the 
applicant, in writing, of the denial of the application, and of the 
applicant's right to review the denial.  The written notice of denial will be 
set forth in a manner designed to be understood by the employee, and will 
include specific reasons for the denial, specific references to the Plan 
provision upon which the denial is based, a description of any additional 
material or information necessary for the applicant to perfect the claim 
along with an explanation as to why such information is necessary and an 
explanation of the Plan's claim procedure.

     This written notice will be given to the employee within 90 days after 
the Plan Administrator receives the application, unless special circumstances 
require an extension of time, in which case, the Plan Administrator has up to 
an additional 90 days for processing the application.  If an extension of 
time for processing is required, written notice of the extension will be 
furnished to the applicant before the end of the initial 90-day period.

     This notice of extension will describe the special circumstances 
necessitating the additional time and the date by which the Plan 
Administrator is to render its decision on the application.  If written 
notice of denial of the application for benefits is not furnished within the 
specified time, the application shall be deemed to be denied.  The applicant 
will then be permitted to appeal the denial in accordance with the Review 
Procedure described below.

     (c)  REQUEST FOR A REVIEW.  Any person (or that person's authorized 
representative) for whom an application for benefits is denied (or deemed 
denied), in whole or in part, may appeal the denial by submitting a written 
request for a review to the Plan Administrator within 60 days after the 
application is denied (or deemed denied).  The Plan Administrator will give 
the applicant (or his or her representative) an opportunity to review 
pertinent documents in preparing a request for a review.  A request for a 
review shall be in writing and shall be addressed to:  
                                          
                          Vice President, Human Resources
                                   CoCensys, Inc.
                                201 Technology Drive
                              Irvine, California 92618
                                          
A request for review must set forth all of the grounds on which it is based, 
all facts in support of the request and any other matters that the applicant 
feels are pertinent.  The Plan Administrator may require the applicant to 
submit additional facts, documents or other material as it may find necessary 
or appropriate in making its review.

     (d)  DECISION ON REVIEW.  The Plan Administrator will act on each 
request for review within 60 days after receipt of the request, unless 
special circumstances require an extension of time (not to exceed an 
additional 60 days), for processing the request for a review.  If an 
extension for review is required, written notice of the extension will be 
furnished to the applicant within the initial 60-day period.  The Plan 
Administrator will give prompt, written notice of its decision to the 
applicant.  In the event that the Plan Administrator confirms the denial of 
the application for benefits in whole or in part, the notice will outline, in 
a manner calculated to be

                                       6.
<PAGE>

understood by the applicant, the specific reasons for the decision and the 
specific Plan provisions upon which the decision is based.  If written notice 
of the Plan Administrator's decision is not given to the applicant within the 
time prescribed in this Section 10(d), the application will be deemed denied 
on review.

     (e)  RULES AND PROCEDURES.  The Plan Administrator will establish rules 
and procedures, consistent with the Plan and with ERISA, as necessary and 
appropriate in carrying out its responsibilities in reviewing benefit claims. 
 The Plan Administrator may require an applicant who wishes to submit 
additional information in connection with an appeal from the denial (or 
deemed denial) of benefits to do so at the applicant's own expense.

     (f)  EXHAUSTION OF REMEDIES.  No legal action for benefits under the 
Plan may be brought until the claimant has (i) submitted a written 
application for benefits in accordance with the procedures described by 
Section 10(a) above, (ii) been notified by the Plan Administrator that the 
application is denied (or the application is deemed denied due to the Plan 
Administrator's failure to act on it within the established time period), 
(iii) filed a written request for a review of the application in accordance 
with the appeal procedure described in Section 10(c) above and (iv) been 
notified in writing that the Plan Administrator has denied the appeal (or the 
appeal is deemed to be denied due to the Plan Administrator's failure to take 
any action on the claim within the time prescribed by Section 10(d) above).

SECTION 11. BASIS OF PAYMENTS TO AND FROM PLAN.

     The Company shall pay all benefits under the Plan.  The Plan shall be 
unfunded, and benefits hereunder shall be paid only from the general assets 
of the Company.

SECTION 12. OTHER PLAN INFORMATION.

     (a)  EMPLOYER AND PLAN IDENTIFICATION NUMBERS.  The Employer 
Identification Number assigned to the Company (which is the "Plan Sponsor" as 
that term is used in ERISA) by the Internal Revenue Service is 330538836. The 
Plan Number assigned to the Plan by the Plan Sponsor pursuant to the 
instructions of the Internal Revenue Service is 503.

     (b)  ENDING DATE FOR PLAN'S FISCAL YEAR.  The date of the end of the 
fiscal year for the purpose of maintaining the Plan's records is December 31.

     (c)  AGENT FOR THE SERVICE OF LEGAL PROCESS.  The agent for the service 
of legal process with respect to the Plan is the General Counsel, CoCensys, 
Inc., 201 Technology Drive, Irvine, California 92618.

     (d)  PLAN SPONSOR AND ADMINISTRATOR.  The "Plan Sponsor" of the Plan is 
CoCensys, Inc., 201 Technology Drive, Irvine, California 92618. The "Plan 
Administrator" of the Plan is the Vice President, Human Resources, CoCensys, 
Inc., 201 Technology Drive, Irvine, California 92618.  The Plan Sponsor and 
Plan Administrator's telephone number is (949) 753-6100.  The Plan 
Administrator is the named fiduciary charged with the responsibility for 
administering the Plan.

                                       7.
<PAGE>

SECTION 13. STATEMENT OF ERISA RIGHTS.

     Participants in this Plan (which is a welfare benefit plan sponsored by 
CoCensys, Inc.) are entitled to certain rights and protections under ERISA.  
If you are an Eligible Employee, you are considered a participant in the Plan 
and, under ERISA, you are entitled to:

     (a)  Examine, without charge, at the Plan Administrator's office and at 
other specified locations, such as work sites, all Plan documents and copies 
of all documents filed by the Plan with the U.S. Department of Labor, such as 
detailed annual reports;

     (b)  Obtain copies of all Plan documents and Plan information upon 
written request to the Plan Administrator.  The Administrator may make a 
reasonable charge for the copies;

     (c)  Receive a summary of the Plan's annual financial report, in the 
case of a plan that is required to file an annual financial report with the 
Department of Labor.  (Generally, all pension plans and welfare plans with 
100 or more participants must file these annual reports.)  

     In addition to creating rights for Plan participants, ERISA imposes 
duties upon the people responsible for the operation of the employee benefit 
plan.  The people who operate the Plan, called "fiduciaries" of the Plan, 
have a duty to do so prudently and in the interest of you and other Plan 
participants and beneficiaries.

     No one, including your employer or any other person, may fire you or 
otherwise discriminate against you in any way to prevent you from obtaining a 
Plan benefit or exercising your rights under ERISA.  If your claim for a Plan 
benefit is denied in whole or in part, you must receive a written explanation 
of the reason for the denial.  You have the right to have the Plan review and 
reconsider your claim.

     Under ERISA, there are steps you can take to enforce the above rights.  
For instance, if you request materials from the Plan and do not receive them 
within 30 days, you may file suit in a federal court.  In such a case, the 
court may require the Plan Administrator to provide the materials and pay you 
up to $100 a day until you receive the materials, unless the materials were 
not sent because of reasons beyond the control of the Plan Administrator.  If 
you have a claim for benefits that is denied or ignored, in whole or in part, 
you may file suit in a state or federal court.  If it should happen that the 
Plan fiduciaries misuse the Plan's money or if you are discriminated against 
for asserting your rights, you may seek assistance from the U.S. Department 
of Labor, or you may file suit in a federal court.  The court will decide who 
should pay court costs and legal fees. If you are successful, the court may 
order the person you have sued to pay these costs and fees.  If you lose, the 
court may order you to pay these costs and fees, for example, if it finds 
your claim is frivolous.

     If you have any questions about the Plan, you should contact the Plan 
Administrator.  If you have any questions about your rights under ERISA, you 
should contact the nearest area office of the U.S. Labor - Management 
Services Administration, Department of Labor.

                                      8.
<PAGE>

SECTION 14. EXECUTION.

     To record the adoption of the Plan as set forth herein, effective as of 
March 26, 1998, CoCensys, Inc. has caused its duly authorized officer to 
execute the same on May 13, 1998.

                                COCENSYS, INC.
     
     
                                By:   /s/ F. Richard Nichol, Ph.D. 
                                      -----------------------------------------
                                Title:   President and Chief Executive Officer
                                      -----------------------------------------


                                       9.