30652
Effects of Oxytocin on Biological Motion Perception in Youth with ASD: A MEG Study
The ability to recognize and prefer biological motion is highly conserved and typically developed within the first year of life and is believed to be critical for developing social skills and social understanding. Few studies have shown that infants and adults with autism spectrum disorders (ASD) failed to recognized biological motion, preferred a non-biological stimuli and present atypical brain activity during these tasks. Intranasal administration of the neuropeptide Oxytocin (OT) in individuals with ASD, has been found to modulate the activation of the mirror-neuron system (MNS) and other social-related brain regions, as well as attention to social cues. Here we focused on the influence of OT on the oscillatory brain activity in people with ASD during biological motion perception tasks, especially on alpha-band (mu) activity which is involved in socially-related tasks.
Objectives:
This study aims to explore the impact of OT on oscillatory brain activity in ASD using magnetoencephalography (MEG) during a well-validated biological motion paradigm. We focused mainly on alpha frequency which is considered to represent the MNS activity and correlates with social perception. We hypothesize that OT administration will modulate alpha-band activity in response to biological motion stimuli to resemble that of an aged matched typically developed (TD) group.
Methods:
As a part of an ongoing study, we present initial data from twenty youth with ASD (aged 12-18), who received a single dose of intranasal OT (24IUs) in a double-blind placebo-controlled study. Forty five minutes following administration, participants were scanned in the MEG. During each scan participants were presented with twelve point-light video clips, each 28 s long, presenting figure-performed human action (clapping hands, jumping) or a random movement. An aged-matched TD group serves as a baseline for comparison. For ethical reasons, TD participants did not receive OT/placebo.
Results:
Preliminary results indicate that in ASD, OT indeed modulate the power of alpha band during video clip observation. Calculating the ratio of alpha power between the biological and the random conditions revealed time-dependent differences in the pattern of alpha in sessions with and without OT. Still, with or without OT, ASD individuals presented neural activation patterns different from those of TD.
Conclusions:
Our results indicate that in ASD, OT can influence primary and preserved developmental abilities such as the ability to differentiate biological from non-biological movement. In line with former studies our results imply that OT may attune attention to social stimuli and thus might help to improve social difficulties. To the best of our knowledge this is the first MEG experiment addressing the influences of OT on youth with ASD. Studies of this shade light not only on behavior but also on specific neural component correlates with social perception and thus allow us to learn more about the complex phenomenon of ASD.