Autism interaction

Autism (Pervasive Development Disorder). The association between schizophrenia and autism is of particular historic significance. Bleuler, who coined the term schizophrenia, included autism as one of his four As among the symptoms of schizophrenia, the others being affect, ambivalence, and association. By autism, Bleuler meant the indifference to and separation from normal social interaction that is characteristic of schizophrenia. 

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. 

Thus, the use of some strains should be avoided as their autism-like behavior may prevent the relevance of this test as a model of anxiety. In performing the social interaction test for screening anxiolytic and anxiogenic drugs, it is suggested that the same two mice are not re-introduced into the same environment together, as this may eliminate the social novelty of the condition, and will affect their test performance. 

Bolivar, V. J., Walters, S. R. and Phoenix, J. L. (2007) Assessing autism-like behavior in mice variations in social interactions... 

D Amelio, M., Ricci, I., Sacco, R., Liu, X., D Agruma, L., Muscarella, L.A., Guamieri, V., Militemi, R., Bravaccio, C., Elia, M., Schneider, C., Melmed, R., Trillo, S., Pascucci, T., Puglisi-Allegra, S., Reichelt, K.L., Macciardi, F., Holden, J.J., Persico, A.M. (2005). Paraoxonase gene variants are associated with autism in North America, hut not in Italy possible regional specificity in gene-environment interactions. Mol. Psychiatry 10 1006-16. 

Direct effects on human behaviours by OT have also been reported in past researches. In particular OT seems to increase trust in social interaction (Kosfeld et al., 2005) and to reduce responses to social stress (Heinrichs et al., 2003) and intranasal administration of OT improved the ability to infer the mental state of others from social cues of the eye region (Domes et al., 2007), encouraging researchers to explore whether the so-called trust hormone could represent a potential autism treatment (Opar, 2008). 

The Reelin gene has been implicated in the aetiology of neurodevelopmental disorders such as schizophrenia and autism (Abrahams Geschwind, 2008 Fatemi, 2005 Keller Persico, 2003). Interestingly, a common variant of the Reelin gene has been found to increase schizophrenia risk only in women (Shifman et al., 2008), confirming that gene-sex interactions can be important for neurodevelopmental disorders. 

Following our characterization of NL3 R451C mutants, mice lacking NL4 were also found to exhibit autism-related behavioral abnormalities including social interaction abnormalities and ultrasonic vocalizations (Jamain et al., 2008). The functional consequences of NL4 deletion on synapses have yet to be determined. 

Jamain, S, Radyushkin, K, Hammerschmidt, K, Granon, S, Boretius, S, Varoqueaux, F, Ramanantsoa, N, Gallego, J, Ronnenberg, A, Winter, D, et al. (2008) Reduced social interaction and ultrasonic communication in a mouse model of monogenic heritable autism. Proc Natl Acad Sci USA 105 1710-1715. 

Although the etiology of autism is not understood, the defining or core symptoms of autistic disorder are considered to be impaired social interaction, impaired verbal and nonverbal communication, and restrictive, repetitive patterns of behavior. In addition, most patients with a primary diagnosis of autism exhibit other neurological or psychiatric symptoms, which may include seizures, sleep disorders, anxiety, panic attacks, attention deficit/hyperactivity, self-injury, and cognitive impairment (Simonoff et ah, 2008). It is not known to what extent these comorbidities reflect the primary pathology of autism and to what extent they represent unrelated vulnerabilities that are exacerbated by the impaired social interaction and communication that is characteristic of the disorder. 

Overall, the status of pharmacotherapy for autism remains disappointing. While a number of agents have been found to be somewhat useful in the treatment of ASD, evidence of efficacy with respect to core symptoms of impaired social interactions and communication is weak. The greatest success has been in treating problems of hyperactivity and irritability. It is notable that with the exception of the stimulants, most of the medications that have been found to be effective are to some extent sedative, raising the question of whether the therapeutic effects that have been observed are in fact specific to autism or simply a consequence of nonspecific sedation. The absence of clear effects on core symptoms means that pharmacology has thus far provided few clues as to the neurochemical basis of ASD. 

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... 

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