It’s interesting you’d say that because I always understood the term Shell Shock to have been abandoned in favor of a more accurate and descriptive term. So I think if it was still in use by psychologists today (for some reason), I would have expected to see that on this list, and see the authors argue for the far more accurate term Post Traumatic Stress Disorder.

As a case in point, this list does include Multiple personality disorder and argues we should instead use the more accurate term dissociative identity disorder.

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Shell shock has a genuinely complex and interesting history. It has described different conditions, had different connotations and value judgements, and had different supposed causes over time.

As I understand it, shell shock has at least two very real components: Traumatic brain injury and Post traumatic stress disorder - they are often found together, and they act together to make things much worse than either by themselves. Mainstream understanding of the harm of repeated mild traumatic brain injury is very recent, relatively speaking.