Date of Award


Document Type


Degree Name

Master of Arts (MA)




Previous research has examined the performance of Native American children on cognitive tasks. The results from these studies indicated that Native American children performed poorer on these tests than Caucasian children, especially on the Verbal IQ scale. Research on cognitive tasks have found that time of day affects performance. One area of cognitive function, not yet examined for susceptibility to circadian influence, is that of executive functioning. The present study examined the effects of time of day on executive functioning in Native American children and Non-Native American children. The study sample consisted of thirty Native American children and fifty-four Caucasian children, between the ages of 7 and 13. The children were administered four different executive measures either at 8am or 3 pm.

The results indicated that there were group differences cn the executive functioning tasks, where the Caucasian children performed better than the Native American children. Also, there were time of day differences, where the children tested in the afternoon performed better on the executive function tasks than the children tested in the morning. Future work in this area needs to obtain family social economic status and assess acculturation of the Native American children.