New York—Ninety percent of website visitors noticed Online Publishers Association ad units within the first 10 seconds of landing on a page, according to “Biometric Evaluation: Assessing the Effectiveness of the OPA Ad Unit,” an OPA study released today.

The study also found that 67% of participants returned to looking at large OPA ad units—such as the Pushdown, the Fixed Panel and the XXL Box—after looking at other content on the page. The study also found that 96% of participants pay attention to OPA ad units, while surfing the Web and that 73% of users who fixated on ad units after the first 10 seconds on the page had a stronger emotional response to the ad than to the rest of the page.

Innerscope Research helped OPA conduct the study, which took place this summer and included 100 participants. Innerscope specializes in biometric research, and it tracked participants’ eye movement and vital signs to gauge participants’ emotional response to content as they viewed the home pages of OPA members CNN.com, MSNBC.com and NYTimes.com.