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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 CvJsKsGUBIX/DF0/y5woZClOYLutGUY5TlxGbmxQ1UNUxnHV2jsLcPEcbAORtzdP
 uQMH+F1WD3KuMKqyh40AHQ==

<SEC-DOCUMENT>0001005477-08-003530.txt : 20080521
<SEC-HEADER>0001005477-08-003530.hdr.sgml : 20080521
<ACCEPTANCE-DATETIME>20080521153810
ACCESSION NUMBER:		0001005477-08-003530
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080519
FILED AS OF DATE:		20080521
DATE AS OF CHANGE:		20080521

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ASPECT MEDICAL SYSTEMS INC
		CENTRAL INDEX KEY:			0000886235
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTROMEDICAL & ELECTROTHERAPEUTIC APPARATUS [3845]
		IRS NUMBER:				954154357
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		141 NEEDHAM STREET
		CITY:			NEWTON
		STATE:			MA
		ZIP:			02464-1505
		BUSINESS PHONE:		(617) 559-7857

	MAIL ADDRESS:	
		STREET 1:		141 NEWTON STREET
		CITY:			NEWTON
		STATE:			MA
		ZIP:			02464-1505

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			JUVONEN RONALD
		CENTRAL INDEX KEY:			0001137058

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-24663
		FILM NUMBER:		08851828

	MAIL ADDRESS:	
		STREET 1:		C/O DOWNTOWN ASSOCIATES
		STREET 2:		674 UNIONVILLE ROAD, SUITE 105
		CITY:			KENNETT SQUARE
		STATE:			PA
		ZIP:			19348
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>edgar123.xml
<DESCRIPTION>FORM 3
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2008-05-19</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000886235</issuerCik>
        <issuerName>ASPECT MEDICAL SYSTEMS INC</issuerName>
        <issuerTradingSymbol>ASPM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001137058</rptOwnerCik>
            <rptOwnerName>JUVONEN RONALD</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O DOWNTOWN ASSOCIATES, L.L.C.</rptOwnerStreet1>
            <rptOwnerStreet2>674 UNIONVILLE ROAD, SUITE 105</rptOwnerStreet2>
            <rptOwnerCity>KENNETT SQUARE</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19348</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock, $0.01 par value</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1759433</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By partnerships and limited liability company</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The securities reported herein are held by Downtown Associates I, L.P., Downtown Associates II, L.P., Downtown Associates III, L.P. and Downtown Associates V, L.P. (collectively referred to as the &quot;Downtown Funds&quot;).  The reporting person's indirect interest in the securities held by the Downtown Funds is limited to his pecuniary interest, if any, in the Downtown Funds.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Ronald J. Juvonen</signatureName>
        <signatureDate>2008-05-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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