Is there a relationship between autism and incomplete inversion of the hippocampus?

From the Guidelines

There is no established relationship between autism and incomplete inversion of the hippocampus based on the provided evidence. The provided study 1 discusses various approaches to early screening of autism spectrum disorder, including functional MRI activity, resting state EEG, and blood-based biomarker studies. However, it does not mention any specific relationship between autism and incomplete inversion of the hippocampus. Some key points from the study include:

• Toddlers with autism spectrum disorder (ASD) exhibit significantly weaker interhemispheric correlations in the inferior frontal gyrus and superior temporal gyrus compared to other groups 1.
• Infants at high risk for autism exhibit a different developmental trajectory than typically developing control subjects, with differences most evident between 9 and 12 months of age 1.
• Evoked responses to dynamic gaze at 8 months in high-risk infants were predictive of an ASD diagnosis at 36 months 1.
• Blood-based biomarker studies of ASD have yet to reveal themselves as viable screening approaches due to the relatively low rates of discovered genetic mutations in the ASD population 1. Given the lack of direct evidence, it is essential to prioritize caution and consider the complexity of autism spectrum disorders, which are influenced by multiple factors. In real-life clinical practice, it is crucial to focus on established screening methods and diagnostic criteria for autism, rather than relying on unconfirmed associations with specific brain structures like the hippocampus.

From the Research

Relationship Between Autism and Incomplete Inversion of the Hippocampus

• There is evidence to suggest that the hippocampus is affected in individuals with autism spectrum disorder (ASD), with impairments in hippocampus-dependent learning, memory, language ability, emotional regulation, and cognitive map creation 2, 3, 4.
• However, the relationship between autism and incomplete inversion of the hippocampus (IHI) is not directly addressed in the provided studies.
• IHI has been associated with several neuropathological conditions, including epilepsy, and is thought to be a factor of susceptibility to hippocampal sclerosis and loss of volume 5, 6.
• One study found that IHI was present in 23.3% of healthy participants, with no significant relationships between whole hippocampal volumes and IHI, but significant relationships between the volumes of the left and right cornu ammonis subfield-1 (CA1) and IHI scores 5.
• Another study found that IHI was more frequent in patients with epilepsy, particularly in certain epilepsy syndromes, but no causality between temporal lobe epilepsy and IHI could be found 6.
• While there is no direct evidence linking autism to IHI, the hippocampal abnormalities observed in ASD individuals may be related to the developmental syndrome of hippocampal dysfunction, which could potentially be associated with IHI 3, 4.