I had never heard of SCD before researching all of this. Roughly SCD looks like autism category A behaviors without category B. It is basically ASD’s social components without the repetitive behaviors.

You can read more about it here:

• Autism Speaks

The “Pragmatic” part is about a communication disability:

Pragmatics refers to using language in proper context. For example, it’s important for children to develop the ability to use language differently when playing with, say, a younger child versus a teacher.

The DSM 5 defines SCD in terms of behavior, not mechanism.

Here are the criteria from the DSM 5:

1. Deficits in using communication for social purposes, such as greeting and sharing information, in a manner that is appropriate for the social context.

2. Impairment of the ability to change communication to match context or the needs of the listener, such as speaking differently in a classroom than on a playground, talking differently to a child than to an adult, and avoiding use of overly formal language.

3. Difficulties following rules for conversation and storytelling, such as taking turns in conversation, rephrasing when misunderstood, and knowing how to use verbal andnonverbal signals to regulate interaction.

4. Difficulties understanding what is not explicitly stated (e.g., making inferences) and nonliteral or ambiguous meanings of language (e.g., idioms, humor, metaphors, multiple meanings that depend on the context for interpretation).

Additionally, these should result in functional limitations in communication, social activity, academics or occupational performance.

My Experience

Again, I am not expert on neurodevelopmental disorders, so I am interpreting through my own lens with the help of an LLM.

As noted above, I have strong overlap on ASD Category A and none on Category B. Examining the points above:

Point 1 – Greeting

Using my Functional Cognitive Architecture I have a zero lag “greet people in the hallway” script. If I am not paying attention I can fall prey to the “how are you doing?” being taken literally. I think slight impairment beyond any emotional mirroring that might be expected.

Point 2 – Context / Pragmatism

At worst I presume people to have knowledge that they might not have. I can usually detect this (“huh?”) and adjust on the fly to explain the unfamiliar parts (this tends to land better than mansplaining in my experience). Certainly I carefully consider the audience for something important: what do I think they know, and what information do they need to reach the conclusion I want? It isn’t automatic, but I think I am capable.

Point 3 – Taking Turns

I do sometimes talk over people but will back off if we collide. I don’t have the Social Salience to pick up the nonverbal cues, I wait for silence and attempt to go (like a network). Again slight impairment as it isn’t automatic, but functional in practice.

Point 4 – Non-Literal Understanding

This might be my weakest point: I prefer literal communication and can struggle without it, especially when it comes to Theory of Mind – I can’t tell what others are thinking unless they tell me.

• I understand common idioms and can use them
• inference is OK if I have the inputs and can follow the logic
• metaphors are less obvious to me, though hitting-over-the-head obvious ones work

Some impairment, but day-to-day use is functional.

Diagnostic

The LLM tried some diagnostic questions, this is one:

If you are provided with a 100% literal, text-based manual for a specific social interaction, can you execute it with 100% accuracy?

I think of this as a flowchart for the meeting. Aside from my normal lack of social salience, sure I can easily follow directions.

Per the LLM, if you have SCD the pragmatic disability means:

struggle to apply the rules because the underlying logic of communication is fractured

My Conclusion

On closer examination I believe I don’t have SCD.

• there is some overlap in the 4 items
• but in my opinion no functional limitations
• however, deeper understanding between my wife and I do suffer from my lack of Social Salience
• lack of impact: does not match SCD expectations
  • married for over 20 years
  • long term employee as a high level software engineer

Certainly I think the mechanism (failure of the pragmatic processing) does not exist – my failures are due to lack of signal, not processing failure.