The Biology of Social Functioning

Social interactions are a big part of autism. Dr. Karen Parker is an integral researcher into this field, studying what causes the differences between neurotypical and autistic individuals. The following study demonstrates the similar effects of a certain biological difference, but it does not necessarily attribute the difference to the cause of autism. 

The Study

Dr. Parker started out with the question: what creates maternal love? MRI scans of the brain demonstrated bursts of oxytocin (OXT) whenever a mother gave birth to a child. Oxytocin is a hormone involved in the uterine contractions when giving birth as well as providing milk to the newborn. Furthermore, arginine vasopressin, a molecule similar to OXT, was a subject of the study.

The model of OXT as strengthening social bonds, like the one between mother and child, was a valuable suggestion to Dr. Parker. Thus, she proposed that individuals with more OXT receptors than others (hormones are chemical compounds in the body that perform actions when they combine to receptors, molecules that activate responses within the cell) could be more social than others.

Dr. Parker came to this theory after observing the differences between Prairie Voles and Montane Voles. Prairie voles were extremely sociable and liked to interact. However, Montane voles liked to be more isolated. When studying each animal, it was found that there were OXT receptors in Prairie voles than Montane voles.

Consequently, Dr. Parker performed human trials with nasal injections of OXT. She found that those injections resulted in less anxiety, higher eye contact, and higher demonstrations of empathy. Conversely, decreasing OXT levels resulted in a lower level of social recognition. The syndromes present in lower OXT cases were similar to the conditions of autistic individuals.

The specific of the study were as follows. The study was a double blind trial, meaning that the researchers did not know if they were giving the participants OXT or a simple placebo as to assure randomness and more precise results. The eligibility of the trial was an age range of 6 to 12 years old, an IQ rating of greater than 40, being autistic, having a normal EKG, and a good medical health record. The initial number of people in the trial was 54 people. Eligibility assessments reduced the count to 35 people. 17 people received OXT, and the remaining 18 received a placebo. The hypothesis formed was that the people with the greatest level of OXT would benefit the most. The results of the study were as follows. There was no difference in vital signs, yet there was an improvement in social responsiveness.

As of now, the study was proved to not be repeatable. Furthermore, animal models cannot always be applied to human models.

A new model was proposed that wished to study monkeys. A reserve of monkeys in the Davis Primate Center, California proved to be integral in carrying out this study. Young male monkeys were exclusively studied as the subjects of the study. It carried a social responsiveness scale for the monkeys based on natural tasks, ability to recognize faces, and interaction with peers. Because there were so many monkeys, extreme populations were able to be examined.

The biomarkers studied were cerebrospinal fluid, oxytocin, and arginine vasopressin. Only vasopressin levels differed in low social and high social populations. Because the study was recent, a new study is in the process of being formed. Just like when OXT was nasally injected (through the nose), it may be possible to nasally inject vasopressin. The tolerability and test safety have yet to be examined.

Conclusion

Overall, the study proved instrumental in opening new doors and crafting new questions that could be concretely answered. In the search for answers, the exploration typically results in new questions that need to be unanswered. Like a crossword, we hope that one day all the boxes will be filled. As for now, we must reiterate that the symptoms demonstrated in this study were similar to those in autistic individuals. However, they were not necessarily the same causes. Questions about the cause remained to be answered.