When Gary recalls a negative memory, he re-experiences the emotion he felt, and gets upset. Since he is prone to obsessive thinking, once a negative emotion triggers, he can obsess about it — and stay upset — for hours.

Tabitha gets trauma flashbacks. She re-experiences events so vividly that they re-traumatize her. Afterward fear, anxiety, depression, and crying jags can debilitate her for days, and affect her mood for weeks.

Emotionally loaded recall is especially common in people with Borderline Personality Disorder (BPD), a learned trauma response. It’s also common among people with Asperger syndrome. Like Gary, Aspies are prone to obsess over negative emotions and make them worse.

Of course, re-experiencing remembered emotions can be an asset when you recall pleasant memories. But with negative experiences — especially traumas — it’s usually preferable to get the useful life lessons from less-than-positive memories, without getting upset or re-traumatized.