Lacunar amnesia
Lacunar amnesia was a psychological condition and form of amnesia that occurred when a patient witnessed an act of violence so horrible that instead of processing it normally, they acted as though it had not happened.

Dr. McCoy's preliminary diagnosis included lacunar amnesia when he assessed the lack of grief shown by the orphaned children of the Starnes Exploration Party on planet Triacus after the death of their parents in 2268. ()

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Medical conditions