Results from Aspect's Cape Cod Memory Study Presented at the International Conference on Alzheimer's Disease and Related Disorders.

NEWTON, Mass. -- Aspect's EEG-based Technology May be More Repeatable than Standard Cognitive Tests, Impact of Alzheimer's Disease Medications Observed

Aspect Medical Systems presented two abstracts at the International Conference on Alzheimer's Disease and Related Disorders (ICAD), being held in Madrid, Spain July 15 -20, 2006. The abstracts highlight findings from Aspect's 205 patient "Cape Cod Memory Study" investigating Aspect's EEG-based technology ("BIS-AD") as a measure and potential predictor of cognitive decline in normal elderly patients. According to the Alzheimer's Association, the sponsor of the ICAD conference, 4.5 million people suffer from Alzheimer's disease in the United States alone, and this figure could triple by 2050.

On Monday, July 17, Aspect presented an abstract entitled, "Baseline Assessment of EEG BIS-AD in Longitudinal Trial Predicts Subjects Who Later Sought Pharmacological Cognitive Therapy." Four of the 205 normal elderly subjects enrolled in the Cape Cod study were subsequently prescribed treatment with Alzheimer's disease medications. The baseline BIS-AD values for these four subjects were significantly lower as compared to other study subjects, and BIS-AD values increased for the three subjects whose cognition improved and decreased for the one subject whose cognition worsened at their first visit after treatment had been initiated. "This is the first analysis from our Cape Cod study that demonstrates the potential value of the technology in tracking the effects of medications for Alzheimer's disease," said Scott Greenwald, Ph.D., Vice President of Research at Aspect. "We plan to pursue additional research exploring BIS-AD as a biomarker of treatment response in Alzheimer's disease."

The second abstract, presented at the "Hot Topics" poster session today, Wednesday, July 19, demonstrated that Aspect's technology is free of the "learning effects" that plague standard cognitive assessment tests. Learning effect occurs when patients are able to improve their performance on a cognitive test through repetition, so that the connection between the patient's test score and their actual cognitive status may become weaker with each test iteration. Data from the Cape Cod Memory Study revealed that Aspect's BIS-AD measurement for cognitively normal elderly subjects remained stable across three recordings administered over a six-month period, whereas these same subjects' scores on the Mini Mental State Evaluation (MMSE) and Alzheimer's Disease Assessment Scale (ADAScog) improved over the same time period. The trend variation between BIS-AD and the cognitive scales can be attributed to learning effect, since improvement in cognitive function would generally not be expected in this population and timeframe. The abstract also reaffirms earlier findings from the Cape Cod Memory Study that subjects' BIS-AD measurement correlates with MMSE and ADAS-cog at baseline when subjects first enter the study, further supporting the notion of a learning effect.

According to Vikas Saini, M.D., principal investigator of the Cape Cod Study, "The fact that patients can improve their scores on cognitive assessment tests such as the MMSE and ADAS-cog through repetition limits the value of these tools in monitoring patients over time." Research indicates that the MMSE and similar tests are also subject to variable results depending on a patient's baseline education level and language skills, making the diagnosis of mild cognitive impairment or dementia difficult in many patients. "I believe that early and accurate detection of changes in cognitive function through objective brain assessment tools will become increasingly important, particularly as disease-modifying treatments for Alzheimer's disease become available," emphasized Dr. Saini.

Aspect's research technology for assessment of cognitive function employs a proprietary algorithm that interprets brain electrical activity transmitted from a sensor placed non-invasively on the patient's forehead. In addition to the longitudinal Cape Cod Memory Study, Aspect is pursuing research trials in patients with mild cognitive impairment and Alzheimer's patients pre- and post-treatment with cognitive enhancing medications.

About Aspect Medical Systems, Inc.

Aspect Medical Systems, Inc. (NASDAQ: ASPM) is a global market leader in brain monitoring technology. To date, the Company's Bispectral Index (BIS) technology has been used to assess more than 15.2 million patients and has been the subject of approximately 2,500 published articles and abstracts. BIS technology is installed in approximately 70 percent of hospitals listed in the July 2005 U.S. News and World Report ranking of America's Best Hospitals and in approximately 47 percent of all domestic operating rooms. In the last twelve months, BIS technology was used in approximately 14 percent of all U.S. surgical procedures requiring general anesthesia or deep sedation. BIS technology is available in more than 160 countries. Aspect Medical Systems has OEM agreements with seven leading manufacturers of patient monitoring systems. The company is also investigating how other methods of analyzing brain waves may aid in the diagnosis and management of neurological diseases, including depression and Alzheimer's disease. For more information, visit Aspect's Web site at http://www.aspectmedical.com.

Safe Harbor Statement

Certain statements in this release are forward-looking and may involve risks and uncertainties, including statements regarding the potential value of Aspect's BIS-AD technology in both measuring and predicting cognitive decline in elderly patients and tracking the effects of medications for Alzheimer's Disease and the size of the Alzheimer's Disease market. There are a number of important factors that could cause actual results to differ materially from those indicated by these forward-looking statements. For example, there can be no assurance that future clinical studies, including the Cape Cod Memory Study, will yield positive results, or that any such product will be successfully developed or achieve regulatory approval. The Company also faces other barriers to market penetration and acceptance. The Company may not be able to compete with new products or alternative techniques that may be developed by others, including third-party monitoring products approved by the FDA, and also faces competitive and regulatory risks relating to its ability to successfully develop and introduce enhancements and new products. There are additional factors that could cause the Company's actual results to vary from its forward-looking statements, including without limitation those set forth under the heading "Risk Factors" in the Company's Quarterly Report on Form 10-Q for the fiscal quarter ended April 1, 2006, as filed with the Securities and Exchange Commission. In addition, any forward-looking statements represent the Company's views only as of the date of this press release and should not be relied upon as representing the Company's views as of any subsequent date. While the Company may elect to update forward-looking statements in the future, it specifically disclaims any obligation to do so, even if its expectations change. Therefore, you should not rely on these forward-looking statements as representing the Company's views as of any date subsequent to the date of this press release.

Aspect, Bispectral Index and BIS are registered trademarks of Aspect Medical Systems, Inc. All other trademarks, service marks and company names are the property of their respective owners.

The Web sites identified herein are not incorporated into this press release.