Researchers Find A Key Reason Why Kids With Autism Have Difficulty Interpreting Tone Of Voice

Autism Spectrum Disorder — a developmental disorder in the brain characterized by a wide range of conditions — affects nearly one in 100 children, according to the World Health Organization. While autism can manifest in many different ways, more often than not, people with autism find social interactions particularly difficult to navigate (per Centers for Disease Control and Prevention).

When someone speaks to us, a part of the brain called the superior temporal cortex helps us to pick up on the emotional cues in the voice of the speaker. A 2010 study published in Neuron found that in infants as young as 7 months, this skill is already being developed. However, for many children and adults with autism, deciphering the emotion hidden behind the words spoken to them can prove to be a massive challenge. Until now, experts have had a hard time understanding why.

In a new study published in Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, researchers were able to link this lapse in understanding to a connectivity issue in the brain — information they hope can one day lead to the development of therapies that will help children with autism enhance their social skills (per Stanford Medicine).

Brain connectivity and autism

While the tendency for people with autism to struggle with understanding certain emotional cues is widely understood, the reason for the disconnect has been hard to determine. U.S. News explains that this is because another common symptom of autism is an oversensitivity to stimuli, including lights, textures, and sounds. Until now, it's been unclear whether the issue stemmed from an issue with processing auditory information or a misinterpretation of the information received.

The study, which included 43 children (with and without autism) between the ages of 7 and 12, used magnetic resonance imaging (MRI) to examine how the participants' brains responded to phrases said with different intonations. Daniel Abrams, co-author of the study, explained that while the part of the brain responsible for "hearing" reacted similarly in both neurotypical kids and kids with autism, "what was atypical in kids with autism was the way this signal is getting to a crucial social brain region," (per Stanford Medicine).

Abrams is referring to the temporoparietal junction (TPJ), a part of the brain that helps us to discern the mental states of others (per MasterClass). The research indicates that in children with autism, the connection between the "hearing" center of the brain and the TPJ is stronger than in neurotypical children (per Stanford Medicine). Abrams notes that when it comes to brain connectivity, a delicate balance must be maintained. When parts of the brain are "under- or over-connected," issues like the one detailed here often arise.