Publication Date



Open access

Embargo Period


Degree Type


Degree Name

Master of Science (MS)


Psychology (Arts and Sciences)

Date of Defense


First Committee Member

Heather A. Henderson

Second Committee Member

Philip M. McCabe

Third Committee Member

Michael L. Cuccaro


There is extensive research focused on identifying predictors of autism, including biomarkers such as genes and neurophysiology. Because of inconsistent data, I explored these biomarkers as predictors of variability in behavioral outcomes (i.e., internalizing and externalizing symptoms), rather than indicators of the disorder per se. In a sample of children (ages 8-16) diagnosed with High Functioning Autism (HFA) and an age- and IQ- matched typically developing comparison group, individual differences in behavioral outcomes were assessed in relation to common genetic polymorphisms, 5-HTTLPR and DRD4, and neurophysiological (ERN) and behavioral (rate of self-correction) measures of response monitoring. Although the diagnostic groups did not differ on allele frequency for 5-HTTLPR, carriers of the L variant displayed attenuated ERN amplitudes at frontal-central sites, lower rates of self-correction following errors, and higher levels of parent-reported Somatization and Hyperactivity. With respect to DRD4, an overrepresentation of the 7-repeat allele was found in the HFA sample. Regardless of diagnostic group, 7-repeat allele carriers were rated as having more attention problems. These results suggest that genetics and neural correlates of response monitoring may explain interindividual variations in social emotional functioning of both HFA and typically developing children alike. However, contrary to hypothesis, response monitoring did not mediate the association between 5-HTTLPR or DRD4 and outcome measures. Future directions of this research may look at how genes and measures of response monitoring affect etiology, course, and treatment of autism and other related disorders.


5-HTTLPR; DRD4; Response Monitoring; HFA