Weak Central Coherence Theory of Autism

Caveat: There is no single theory that can fully explain autism. 

The Weak Central Coherence Theory posits that autistics exhibit a cognitive processing style characterized by a propensity for local over global information processing. This theory suggests that autistics have a heightened focus on fine details at the expense of integrating these details into a coherent whole. 

The Weak Central Coherence Theory provides a framework for understanding the distinct cognitive processing style in autism, characterized by a bias toward local over global processing. Neurobiological evidence supports this theory, showing enhanced local processing capabilities and impaired global integration due to altered neural connectivity. This theory helps explain the strengths and challenges faced by individuals with autism in various cognitive and social domains.

Key Concepts

  1. Detail-Focused Processing:

    • Cognitive Tendency: Autistics demonstrate superior performance on tasks requiring attention to fine details, suggesting an enhanced local processing bias.
    • Neurobiological Basis: Neuroimaging studies indicate increased activation in primary and secondary sensory cortices, particularly the visual cortex, which may underlie this enhanced local processing.
  2. Reduced Global Integration:

    • Cognitive Deficit: There is a relative impairment in synthesizing details into a unified, overarching context, which affects higher-order cognitive tasks.
    • Neurobiological Basis: This deficit is associated with reduced long-range connectivity and synchronization between frontal and posterior brain regions, impairing the integration of information across neural networks.
  3. Neuroanatomical Correlates:

    • Prefrontal Cortex: Involvement in executive functions and global processing is diminished, contributing to difficulties in integrating complex information.
    • Posterior Regions: Including the occipital and parietal lobes, these regions exhibit enhanced local processing but reduced integration with other cortical areas.

Examples and Implications

  1. Perceptual Tasks:

    • Enhanced Performance: Autistic individuals often excel at visual search tasks, identifying small differences in stimuli more quickly and accurately than neurotypical individuals.
    • Impaired Performance: They may struggle with tasks that require understanding the overall context, such as interpreting ambiguous figures or scenes.
  2. Cognitive Tasks:

    • Strengths: Detail-oriented tasks like pattern recognition or mechanical assembly are areas of strength.
    • Weaknesses: Tasks requiring abstract thinking, such as comprehending proverbs or making inferences, present challenges due to impaired global processing.
  3. Social Interaction:

    • Implications: Social difficulties can arise from an inability to integrate social cues into a cohesive understanding of social interactions. This can lead to literal interpretations of language and difficulties with nonverbal communication.

Neuroimaging Evidence

  1. Functional MRI (fMRI):
    • Findings: fMRI studies show atypical activation patterns in the frontal and parietal regions during tasks requiring global processing.
  2. Diffusion Tensor Imaging (DTI):
    • Findings: DTI studies indicate atypical white matter integrity, suggesting disrupted long-range connectivity essential for global information integration.
  3. EEG/MEG:
    • Findings: EEG and MEG studies reveal reduced coherence and synchronization across distant brain regions, supporting the notion of impaired global processing.
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Who Autism Research Leaves Out

"It’s time for researchers and technologists to rethink their methodologies and technologies, and explore other innovative approaches to give all members of the autistic community the care we need."
-Hari Srinivasan, Time

 

 https://www.psychologytoday.com/us/blog/giving-voice/202402/the-spectrum-of-loss-grief-through-the-autistic-lens



Congratulations, Hari, from the entire Frist Center Family. We are excited to see the results of your research!


FCAI Neurodiversity Inspired Science and Engineering Fellow Hari Srinivasan has been awarded the 2024 Autistic and Neurodivergent Scholars Working for Equity in Research (ANSWER) Scholars Program Award for his project “Navigating the Near: Virtual Reality Investigations of Peripersonal Space in Autism.” Srinivasan will receive a $10,000 award next academic year to work toward this research.

Hari’s continued outstanding achievements never fail to impress us! Congratulations, Hari, from the entire Frist Center Family. We are excited to see the results of your research!




Backyard Visitors

A deer family (mom and 2 baby deer) frequenting our backyard this summer. The young deer  frolicking, chasing each other and running around is a delight to watch. 


Here is a children's short story I wrote sometime ago.


Poster at CAN 2024

 Yeah, I have another Poster Acceptance for the College Autism Network Summit 2024 in Oct. 

================

From: College Autism Network
Sent: Tuesday, July 16, 2024 2:41 PM
To: Srinivasan, Hari
Subject: College Autism Summit Submission Accepted - Poster

Dear Poster Participant:

We are pleased to inform you that your College Autism Summit submission titled 'Navigating the Near: Virtual Reality Investigations of Peripersonal Space in Autism' has been accepted.

………..

Best,
Amy Radochonski and Cherie Fishbaugh, Program Co-Chairs




Exploring Short-Term Synaptic Plasticity and Its Implications in Autism

Short-term synaptic plasticity, a temporary change in synaptic strength lasting from seconds to minutes, is a crucial mechanism for neural communication and information processing. Two key types of short-term plasticity are paired pulse facilitation (PPF) and paired pulse depression (PPD). Understanding these mechanisms can provide insight into the molecular & genetic underpinnings of autism.

Paired Pulse Facilitation (PPF) occurs when two signals (pulses) arrive in quick succession at a synapse, with the second pulse producing a stronger response than the first. This is due to residual calcium (Ca2+) remaining in the presynaptic terminal after the first pulse, which enhances neurotransmitter release upon the arrival of the second pulse. This phenomenon is particularly significant at synapses with low initial release probability, ensuring that enough neurotransmitters are available for subsequent release.

Paired Pulse Depression (PPD), on the other hand, is characterized by a diminished response to the second pulse. This occurs at synapses with high initial release probability, where the first pulse depletes the readily releasable pool of neurotransmitters, leaving insufficient resources for the second pulse. The timing between the pulses is critical; if the interval is too long, Ca2+ dissipates, and vesicles are replenished, mitigating these effects.

In the context of autism, alterations in short-term plasticity have been linked to the disorder's characteristic neural and behavioral features. Research has shown that mutations in synaptic genes such as SYN1 and SYN2, which regulate synaptic vesicle dynamics, can disrupt short-term plasticity. These mutations result in increased PPF at excitatory synapses and enhanced synaptic depression at inhibitory synapses, leading to an excitatory/inhibitory (E/I) imbalance that contributes to network hyperexcitability and altered neuronal communication (Frontiers, 2015)​ (Frontiers)​.

Furthermore, neuroligin-3 mutations, associated with autism, have been found to differentially alter synaptic function in the hippocampus and cortex. These mutations can increase inhibitory synaptic transmission and disrupt endocannabinoid signaling, further impacting short-term plasticity and neural circuitry (Molecular Psychiatry, 2015)​ (Nature)​. These findings underscore the significant role of short-term plasticity in maintaining neural circuit function and how its disruption can contribute to pathogenesis.

2 versions of this post

For the Academic/Scientific Audience

PlainSpeak in plain language for the lay reader



Independence leading to loneliness and fragmented relationships

  https://time.com/6551520/loneliness-autism-essay/



Transcription Bloopers

Actual Audio: You want to go into superior colliculus a bit more?

Transcription Software: You want to go into the spiritual leaders a bit more.

Audio: So the input is converging. 

Software: So the imprint is converging

 

Disability and Poverty is a tough cycle

In PlainSpeak for Lay Audience

Disability and Poverty: A Tough Cycle

Disability and poverty are closely connected. This makes life harder for disabled people. Here’s why.

  1. Education: Many disabled people don’t get a good education. This makes it hard for them to learn skills needed for good jobs.

  2. Jobs: Disabled people often face problems finding jobs. There aren’t enough job opportunities, and some employers discriminate against them. Without good jobs, it’s hard to earn enough money.

  3. Healthcare: Poor people often can’t afford good healthcare. This can lead to untreated health problems that cause or worsen disabilities.

  4. Support Services: Disabled people need special support, like assistive devices or home modifications, but these can be expensive. Without money, they can’t get the help they need.

The National Council on Disability says that these problems make more disabled people live in poverty. The World Health Organization also says that we need to solve both poverty and disability issues together.

To break this cycle, we need to:

  • Provide better education for disabled people.
  • Create more job opportunities and stop workplace discrimination.
  • Offer better social support services.
  • Make healthcare and housing affordable and accessible for everyone.

When we invest in these areas, we help disabled people live better lives. This also helps reduce poverty and builds a stronger, fairer society for everyone.

2 versions of this post

In PlainSpeak Plain Language for Lay Reader

For Scientific/Academic Audience