Exploring relationships between autistic traits and body temperature, circadian rhythms, and age

Abstract

The number of clinical diagnoses of autism spectrum disorder (ASD) is increasing annually. Interestingly, the human body temperature has also been reported to gradually decrease over the decades. An imbalance in the activation of the excitatory and inhibitory neurons is assumed to be involved in the pathogenesis of ASD. Neurophysiological evidence showed that brain activity decreases as cortical temperature increases, suggesting that an increase in brain temperature enhances the inhibitory neural mechanisms. Behavioral characteristics specific to clinical ASD were observed to be moderated when people with the diagnoses had a fever. To explore the possible relationship between ASD and body temperature in the general population, we conducted a survey study using a large population-based sample (N ~ 2000, in the age groups 20s to 70s). Through two surveys, multiple regression analyses did not show significant relationships between axillary temperatures and autistic traits measured by questionnaires (Autism Spectrum (AQ) and Empathy/Systemizing Quotients), controlling for covariates of age and self-reported circadian rhythms. Conversely, we consistently observed a negative relationship between AQ and age. People with higher AQ scores tended to have stronger eveningness. Our findings contribute to the understanding of age-related malleability and the irregularity of circadian rhythms related to autistic traits.

Effects of focal cortical cooling on somatosensory evoked potentials in rats

“…Recently, autism spectrum disorder (ASD), whose typical symptoms include tactile hypersensitivity, has been associated with an increase in the balance of excitation and inhibition in the cortex (Chen et al, 2020; Kondo and Lin, 2020; Lee et al, 2017; Nelson and Valakh, 2015; Rubenstein and Merzenich, 2003). Interestingly, autistic behaviors have been reported to be relieved during fever in ASD patients (Curran et al, 2007; Good, 2017), although the autistic traits evaluated using questionnaires were shown to have no significant relationship with normal body (axillary) temperatures in the general population (Hidaka et al, 2023).…”