Sadly absolutefy noone in the so called "scientific community" has any fucking clue about panic attacks. Zero. They will babble for days without saying anything.
Listen to this BS that explains nothing basically
" According to the American Psychological Association, the symptoms of a panic attack commonly last approximately thirty minutes. However, panic attacks can be as short as 15 seconds, while sometimes panic attacks may form a cyclic series of episodes, lasting for an extended period, sometimes hours. Often those afflicted will experience significant anticipatory anxiety and limited symptom attacks in between attacks, in situations where attacks have previously occurred. "
However, I do know. Cause I am a "missunderstood genius"

Panic attacks are past life trauma stored and carryed in your DNA or "cellular memory". Sometimes, something you see, hear or experience can trigger those DNA sequences to open and the traumatic memories and all emotional trauma associated with those experiences come in bulk to the surface in the conscious mind. And you a experience seriously overwhelming feelings all of a sudden.
It is a way to "release the past" although not pleasant AT ALL for those who been through it.