Autism neurobiology

Anderson, G.H. (1994). In M.L. Bauman T.L. Kemper (Eds.), The Neurobiology of Autism (227-242). Baltimore John Hopkins University Press. 

Neurobiology of affiliation implications for autism spectrum disorders... 

In human beings and most mammals, affiliation is an essential part of the life process, as it is necessary for both reproduction and survival. There are nonetheless instances in nature of profound lack of affiliative behavior. For example, children with autism spectrum disorders have significant difficulties in social skills, including lack of positive reinforcement from social interaction, poor eye gaze, impairment in social interactions, difficulties in attachment, and difficulties in nonverbal and, often, verbal communication. Deficits of this kind have led us to the study of the neurobiology underlying attachment and affiliation. 

Although social attachment and impairment of social behaviors are evident in a wide range of psychopathology, including childhood trauma, personality disorders, and anxiety disorders, an extensive review of this subject is beyond the scope of this chapter. The focus of this section will thus be primarily limited to the neurobiology of affiliation as it relates to autism spectrum disorders. 

Autism is a developmental disorder of early childhood, characterized by social impairment, communication deficits, and compulsive behavior. The diagnostic criteria, epidemiology, and treatment of this disorder are covered elsewhere in this book (see chapter 42). This section focuses primarily on the dimension of social impairment and the neurobiology relevant to this aspect of autism. 

Serotonin involvement. There is substantial evidence supporting abnormal 5-HT function in autism, particularly with regard to both the social deficit and repetitive behavior dimensions of this disorder. Many studies of the neurobiology of autism have focused on 5-HT, which is implicated in the regulation of many functions relevant to autism, such as learning, memory. 

Additionally, an opioid antagonist, naltrexone, has been used to treat children with autism. The results from these studies have been mixed, with some studies showing a mild decrease in hyperactivity and self-injurious behavior, and improved attention (Gillberg, 1995). The children who respond best to this medication appear to have more severe abnormalities in their beta endorphin levels (Bouvard et al., 1995). Overall, the research suggests that the endogenous opioid system, which is important in the reward aspects of affiliation, may also play a role in the neurobiology of autism. 

Young, J.G., Level, L.I., Newcorn, J.H., and Knott, P.J. (1987) Genetic and neurobiological approaches to the pathophysiology of autism and the pervasive developmental disotdets. In Meltzer, H.Y, ed. Psychopharmacology The Third Generation of Progress. New York Raven Press, pp. 825-836. 

McDougle, C.J., Posey, D.J., and Potenza, M.N. (in press) Neurobiology of serotonin function in autism. In Hollander, E. and Delaney, K., eds. Diagnosis and Treatment of Autism. New York Marcel Dekker. 

DiCicco-Bloom E, Lord C, Zwaigenbaum L, Courchesne E, Dager SR, Schmitz C, Schultz RT, Crawley J, Young LJ (2006) The developmental neurobiology of autism spectrum disorder. J Neurosci 26 6897-6906. 

Acosta MT, Pearl PL (2003) The neurobiology of autism new pieces of the puzzle. Curr Neurol Neurosci Rep 3 149-156... 

Anderson GM (2005) Serotonin in autism. In Bauman ML, Kemper TL (eds) The Neurobiology of Autism. Johns Hopkins University Press, Baltimore, MD, pp 303-318... 

Bailey A, PhUlips W, Rutter M (1996) Autism towards an integration of clinical, genetic, neuropsychological and neurobiological perspectives. J Child Psychol Psychiatry 37 89-126... 

The Male Prevalence in Autism Spectrum Disorders Hypotheses on its Neurobiological Basis... 

Keller F, Persico AM (2003) The neurobiological context of autism. Mol Neurobiol 28 1-22. 

Lord C, Schopler E (1987) Neurobiological implications of Sex differences in Autism. In Neurobiological issues in Autism ( Schopler E and Mesibow GB ed.), Plenum. 

BachevaMer J (2005) The orbitofrontal-amygdala system in nonhuman primates function, development, and early insult. In The neurobiology of autism, second edition (Bauman ML, Kemper TL, eds), pp. 177-189. Baltimore Johns Hopkins University Press. 

Oxytocin and Autism Preliminary Evidence and Neurobiological Mechanisms... 

The strong male prevalence of autism spectrum disorders represents a challenge to any neurobiological theory of autism. Current genetics does not offer clues to this... 

Disturbed social interaction is a central feature of autism and is the source of many of the everyday impairments of patients, their relatives, and their caregivers. Therefore, it made and still makes sense to study the neurobiology of social function. In addition to helping us understand the disorder, this also holds promise for defining targets that could lead to new and more targeted treatments. An excellent... 

Editor Gene J. Blatt Laboratory for Autism Neuroscience Research Department of Anatomy and Neurobiology Boston University School of Medicine 72 East Concord Street Boston, MA 02118-2526 USA... 

---