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                                                                   EXHIBIT 10.30

                                 FIRST AMENDMENT
                                       TO
                           LOAN AND SECURITY AGREEMENT

This First Amendment to Loan and Security Agreement (the "Amendment") is entered
into as of September 29, 2004, by and between COMERICA BANK ("Bank") and
SCIENTIFIC LEARNING CORPORATION ("Borrower").

                                    RECITALS

      Borrower and Bank are parties to that certain Loan and Security Agreement
dated as of January 15, 2004 (as amended from time to time, together with any
related agreements, the "Agreement"). Hereinafter, all indebtedness owing by
Borrower to Bank shall be referred to as the "Indebtedness." The parties desire
to amend the Agreement in accordance with the terms of this Amendment.

      NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

                                    AGREEMENT

I.    INCORPORATION BY REFERENCE. The Recitals and the documents referred to
      therein are incorporated herein by this reference. Except as otherwise
      noted, the terms not defined herein shall have the meaning set forth in
      the Agreement.

II.   AMENDMENT TO THE AGREEMENT. Subject to the satisfaction of the conditions
      precedent as set forth in Article IV hereof, the Agreement is hereby
      amended as set forth below.

      A.    The definition of "Revolving Maturity Date" in Section 1.1 of the
            Agreement is hereby amended and restated to read as follows:

            "Revolving Maturity Date" means July 14, 2005.

      B.    The second paragraph of Section 6.7 of the Agreement is hereby
            amended and restated to read as follows:

            "Borrower shall maintain its primary operating and investment
            accounts with Bank and/or Comerica Securities, Inc., provided,
            however that amounts in excess of Five Million Dollars
            ($5,000,000.00) in the aggregate may be maintained at third party
            institutions."

      C.    The first sentence of Section 6.8 of the Agreement is hereby amended
            and restated to read as follows:

            "Borrower shall maintain at all times a ratio of unrestricted cash
            and cash equivalents maintained at Bank or at Bank's affiliates
            covered by control agreements in form and substance satisfactory to
            Bank, plus net trade accounts receivable less than 90 days from
            invoice date to Current Liabilities less non-refundable deferred
            revenues plus (to the extent not already included therein) all
            Indebtedness to Bank, of at least 1.25 to 1.00."

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      D.    Bank's addresses for notices set forth in Section 10 of the
            Agreement are hereby amended in their entirety to read as follows:

            "If to Bank:                   Comerica Bank
                                           2321 Rosecrans Ave., Suite 5000
                                           El Segundo, CA 90245
                                           Attn:  Manager
                                           FAX: (310) 297-2290

            With a copy to:                Comerica Bank
                                           5 Palo Alto Square, Suite 800
                                           3000 El Camino Real
                                           Palo Alto, CA 94306
                                           Attn: Rod Werner
                                           FAX: (650) 213-1710"

      E.    A new Section 13 is hereby added to the Agreement to read as
            follows:

            "13.  Reference Provision.

                  The parties prefer that any dispute between them be resolved
            in litigation subject to a Jury Trial Waiver as set forth in the
            Loan Documents (defined below), but the availability of that process
            is in doubt because of the opinion of the California Court of Appeal
            in Grafton Partners LP v. Superior Court, 9 Cal.Rptr.3d 511. This
            Reference Provision will be applicable until the California Supreme
            Court completes its review of that case, and will continue to be
            applicable if either that court or a California Court of Appeal
            publishes a decision holding that a pre-dispute Jury Trial Waiver
            provision similar to that contained in the Loan Documents is invalid
            or unenforceable. Delay in requesting appointment of a referee
            pending review of any such decision, or participation in litigation
            pending review, will not be deemed a waiver of this Reference
            Provision.

                  Other than (i) nonjudicial foreclosure of security interests
            in real or personal property, (ii) the appointment of a receiver or
            (iii) the exercise of other provisional remedies (any of which may
            be initiated pursuant to applicable law), any controversy, dispute
            or claim (each, a "Claim") between the parties arising out of or
            relating to this Agreement or any other document, instrument or
            agreement between the Bank and the undersigned (collectively in this
            Section, the "Loan Documents"), will be resolved by a reference
            proceeding in California in accordance with the provisions of
            Section 638 et seq. of the California Code of Civil Procedure
            ("CCP"), or their successor sections, which shall constitute the
            exclusive remedy for the resolution of any Claim, including whether
            the Claim is subject to the reference proceeding. Except as
            otherwise provided in the Loan Documents, venue for the reference
            proceeding will be in the Superior Court or Federal District Court
            in the County or District where venue is otherwise appropriate under
            applicable law (the "Court").

                  The referee shall be a retired Judge or Justice selected by
            mutual written agreement of the parties. If the parties do not
            agree, the referee shall be selected by the Presiding Judge of the
            Court (or his or her representative). A request for appointment of a
            referee may be heard on an ex parte or expedited basis, and the
            parties agree that irreparable harm would result if ex parte relief
            is not granted. The referee shall be appointed to sit with all the
            powers provided by law. Each party shall have one peremptory
            challenge pursuant to CCP Section 170.6. Pending appointment of the
            referee, the Court has power to issue temporary or provisional
            remedies.

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                  The parties agree that time is of the essence in conducting
            the reference proceedings. Accordingly, the referee shall be
            requested to (a) set the matter for a status and trial-setting
            conference within fifteen (15) days after the date of selection of
            the referee, (b) if practicable, try all issues of law or fact
            within ninety (90) days after the date of the conference and (c)
            report a statement of decision within twenty (20) days after the
            matter has been submitted for decision. Any decision rendered by the
            referee will be final, binding and conclusive, and judgment shall be
            entered pursuant to CCP Section 644.

                  The referee will have power to expand or limit the amount and
            duration of discovery. The referee may set or extend discovery
            deadlines or cutoffs for good cause, including a party's failure to
            provide requested discovery for any reason whatsoever. Unless
            otherwise ordered, no party shall be entitled to "priority" in
            conducting discovery, depositions may be taken by either party upon
            seven (7) days written notice, and all other discovery shall be
            responded to within fifteen (15) days after service. All disputes
            relating to discovery which cannot be resolved by the parties shall
            be submitted to the referee whose decision shall be final and
            binding.

                  Except as expressly set forth in this Agreement, the referee
            shall determine the manner in which the reference proceeding is
            conducted including the time and place of hearings, the order of
            presentation of evidence, and all other questions that arise with
            respect to the course of the reference proceeding. All proceedings
            and hearings conducted before the referee, except for trial, shall
            be conducted without a court reporter, except that when any party so
            requests, a court reporter will be used at any hearing conducted
            before the referee, and the referee will be provided a courtesy copy
            of the transcript. The party making such a request shall have the
            obligation to arrange for and pay the court reporter. Subject to the
            referee's power to award costs to the prevailing party, the parties
            will equally share the cost of the referee and the court reporter at
            trial.

                  The referee shall be required to determine all issues in
            accordance with existing case law and the statutory laws of the
            State of California. The rules of evidence applicable to proceedings
            at law in the State of California will be applicable to the
            reference proceeding. The referee shall be empowered to enter
            equitable as well as legal relief, provide all temporary or
            provisional remedies, enter equitable orders that will be binding on
            the parties and rule on any motion which would be authorized in a
            trial, including without limitation motions for summary judgment or
            summary adjudication . The referee shall issue a decision at the
            close of the reference proceeding which disposes of all claims of
            the parties that are the subject of the reference. The referee's
            decision shall be entered by the Court as a judgment or an order in
            the same manner as if the action had been tried by the Court. The
            parties reserve the right to appeal from the final judgment or order
            or from any appealable decision or order entered by the referee. The
            parties reserve the right to findings of fact, conclusions of laws,
            a written statement of decision, and the right to move for a new
            trial or a different judgment, which new trial, if granted, is also
            to be a reference proceeding under this provision.

                  If the enabling legislation which provides for appointment of
            a referee is repealed (and no successor statute is enacted), any
            dispute between the parties that would otherwise be determined by
            reference procedure will be resolved and determined by arbitration.
            The arbitration will be conducted by a retired judge or Justice, in
            accordance with the California Arbitration Act Section 1280 through
            Section 1294.2 of the CCP as amended from time to time. The
            limitations with respect to discovery set forth above shall apply to
            any such arbitration proceeding.

            THE PARTIES RECOGNIZE AND AGREE THAT ALL DISPUTES RESOLVED UNDER
            THIS REFERENCE PROVISION WILL BE DECIDED BY A REFEREE AND NOT BY A
            JURY, AND THAT THEY ARE IN EFFECT WAIVING THEIR RIGHT TO TRIAL BY
            JURY IN AGREEING TO THIS REFERENCE PROVISION. AFTER CONSULTING (OR
            HAVING HAD THE OPPORTUNITY TO CONSULT) WITH COUNSEL OF THEIR OWN
            CHOICE,

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            EACH PARTY KNOWINGLY AND VOLUNTARILY AND FOR THEIR MUTUAL BENEFIT
            AGREES THAT THIS REFERENCE PROVISION WILL APPLY TO ANY DISPUTE
            BETWEEN THEM WHICH ARISES OUT OF OR IS RELATED TO THIS AGREEMENT OR
            THE LOAN DOCUMENTS.

III.  LEGAL EFFECT.

      A.    The Agreement is hereby amended wherever necessary to reflect the
            changes described above. Borrower agrees that it has no defenses
            against the obligations to pay any amounts under the Indebtedness.

      B.    Borrower understands and agrees that in modifying the existing
            Indebtedness, Bank is relying upon Borrower's representations,
            warranties, and agreements, as set forth in the Agreement. Except as
            expressly modified pursuant to this Amendment, the terms of the
            Agreement remain unchanged, and in full force and effect. Bank's
            agreement to modifications to the existing Indebtedness pursuant to
            this Amendment in no way shall obligate Bank to make any future
            modifications to the Indebtedness. Nothing in this Amendment shall
            constitute a satisfaction of the Indebtedness. It is the intention
            of Bank and Borrower to retain as liable parties, all makers and
            endorsers of Agreement, unless the party is expressly released by
            Bank in writing. No maker, endorser, or guarantor will be released
            by virtue of this Amendment. The terms of this paragraph apply not
            only to this Amendment, but also to all subsequent loan modification
            requests.

      C.    This Amendment may be executed in two or more counterparts, each of
            which shall be deemed an original, but all of which together shall
            constitute one instrument. This is an integrated Amendment and
            supersedes all prior negotiations and agreements regarding the
            subject matter hereof. All modifications hereto must be in writing
            and signed by the parties.

IV.   CONDITIONS PRECEDENT. Except as specifically set forth in this Amendment,
      all of the terms and conditions of the Agreement remain in full force and
      effect. The effectiveness of this Agreement is conditioned upon receipt by
      Bank of this Amendment, and any other documents which Bank may require to
      carry out the terms hereof, including but not limited to the following:

      A.    This Amendment, duly executed by Borrower;

      B.    Corporation Resolutions and Incumbency Certification, duly executed
            by Borrower;

      C.    A legal fee from the Borrower in the amount of $250; and

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      D.    Such other documents, and completion of such other matters, as Bank
            may reasonably deem necessary or appropriate.

IN WITNESS WHEREOF, the undersigned have executed this Amendment as of the first
date above written.

                                                SCIENTIFIC LEARNING CORPORATION

                                                By: /s/ Jane A. Freeman
                                                    --------------------------
                                                Title: Chief Financial Officer

                                                COMERICA BANK

                                                By: /s/ Rod Werner
                                                    --------------------------
                                                Title: Vice President

AMENDMENT
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