Brain Disconnectivity
Individuals with ASD have differences in cortical organization (narrower and more densely packed columns of neuronal cells). This suggests that there may be altered structural connectivity and thus the connectivity between different brain structures.
The brain is activated even in it's resting state, and many researchers hypothesize that this resting state is central to nervous system functioning.8 Many studies of the cerebral cortical development in young children with autism have found that the cerebrum and several of its subdivisions grow rapidly in the first few years of life.9, 10, 11 Gray and white matter also have significant growth differences in children with autism, but this may not be significant because gray and white matter tends to differ depending on the region of the brain and gender.9 See White Matter for more information.
Another study of the functional connectivity of the default network in adolescents found that individuals with ASD had significantly weaker connectivity between the PCC and the superior frontal gyri, the PCC and the temporal lobes, and the PCC and the parahippocampal gyri. They also found that weaker connectivity between the PCC and areas listed above was associated with poorer social impairment, and that more severe restrictive and repetitive behaviors were associated with weaker connectivity between the PCC and the medial prefrontal cortex, the PCC and the temporal lobes, and the PCC and the superior frontal gyri. Poorer verbal and non-verbal communicative ability was associated with stronger connectiviety between the PCC and the parahippocampal gyrus, and the PCC and the temporal lobes. The authors suggest that adolescents with ASD may have default networks which develop for a longer time. 7
Citations
Analytical Techniques
