Does erotic stimulus presentation design affect brain activation patterns? Event-related vs. blocked fMRI designs

• Main Authors: Klemen Jane, Vollstädt-Klein Sabine, Bühler Mira, Smolka Michael N
• Format: Article
• Language: English
• Published: BMC 2008-07-01
• Series: Behavioral and Brain Functions
• Online Access: http://www.behavioralandbrainfunctions.com/content/4/1/30

<p>Abstract</p> <p>Background</p> <p>Existing brain imaging studies, investigating sexual arousal via the presentation of erotic pictures or film excerpts, have mainly used blocked designs with long stimulus presentation times.</p> <p>Methods</p> <p>To clarify how experimental functional magnetic resonance imaging (fMRI) design affects stimulus-induced brain activity, we compared brief event-related presentation of erotic vs. neutral stimuli with blocked presentation in 10 male volunteers.</p> <p>Results</p> <p>Brain activation differed depending on design type in only 10% of the voxels showing task related brain activity. Differences between blocked and event-related stimulus presentation were found in occipitotemporal and temporal regions (Brodmann Area (BA) 19, 37, 48), parietal areas (BA 7, 40) and areas in the frontal lobe (BA 6, 44).</p> <p>Conclusion</p> <p>Our results suggest that event-related designs might be a potential alternative when the core interest is the detection of networks associated with immediate processing of erotic stimuli.</p> <p>Additionally, blocked, compared to event-related, stimulus presentation allows the emergence and detection of non-specific secondary processes, such as sustained attention, motor imagery and inhibition of sexual arousal.</p>