For today's episode, we expand on Autism and Sensory Processing. We return to the mesencephalon—a brainstem region with superior and inferior colliculi—as a critical hub for sensory integration and attention bias. We cover four scientific articles, starting with Marco et al. (2011), which uses EEGs, MEGs, and fMRIs to reveal autism’s auditory processing inconsistencies (e.g., delayed N100/M100 cortical responses), tactile hypersensitivity from overactive receptors, and visual processing quirks like reduced fusiform gyrus activation for faces. Russo et al. then explore brainstem-level deficits, showing autistic children’s auditory brainstem responses (ABR) to speech syllables like "DA" exhibit poor neural synchrony and phase locking, especially in noise, due to disrupted wave V, A, D, F timing—linking these to language impairments. These findings point to biological roots, including denser neocortical mini-columns (30-40 vs. 50-60 microns in controls) and cerebellar Purkinje cell loss, impairing local processing and long-range connectivity.

The episode continues with Leekam et al. (2007), confirming over 90% of autistic individuals have multi-modal sensory abnormalities—hypo- and hypersensitivity tied to serotonin and GABA dysregulation—persisting across life, while Tomchek and Dunn (2007) note 95% prevalence via caregiver reports, hinting at neural pathway disruptions. At some point, we need to acknowledge the mesencephalon’s embryological stasis as one of four neural cell types, suggesting its evolutionary role in sensory modulation is key to Autism’s biology. These articles collectively highlight altered neural circuitry, from brainstem to cortex, and biases us to remaining within ourselves. Remember, the biology that gives us Autism allows us to be comfortable within ourselves.

Marco et al 2011 https://www.nature.com/articles/pr9201193

Russo et al 2009 https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1467-7687.2008.00790.x

Leekam et al 2007 https://link.springer.com/article/10.1007/s10803-006-0218-7

Tomchek & Dunn 2007 https://affectautism.com/wp-content/uploads/2016/05/tomcheck_dunn.pdf

0:00 Autism and Sensory Processing; comorbid conditions; Mesencephalon

3:03 Article 1 Marco et al 2011

4:11 Auditory

5:00 N100 & M100 tools

9:17 Tactile

11:23 Visual

13:53 Multisensory Integration

15:16 Postmortem; Cerebellum & Purkinje Cells; Minicolumns

17:06 Speech

19:02 Article 2 Russo et al; Brainstem scientists

20:28 Auditory Brainstem Response (ABR); Quiet versus Noisy environments; Beatles comparison

23:49 Neural Synchrony; Waves V, A, D, F

24:33 Phase Locking

27:34 Article 3 Leekam et al 2007; Neuroplasticity

33:09 Article 4 Tomchek & Dunn 2007

36:36 Reviews/Ratings and Contact Info

X: https://x.com/rps47586

Hopp: https://www.hopp.bio/fromthespectrum

YT: https://www.youtube.com/channel/UCGxEzLKXkjppo3nqmpXpzuA

email: [email protected]