Any idea about seizures?

[Zoe&Nina's Mom]

I rescued my American Staffordshire Terrier, Nina, about 2.5 yrs ago. She was severely under weight, heartworm positive, and had major infections from just giving birth 2 weeks before but not nursing or getting the vet care she needed. Since then, she is now 55lbs. up from 23lbs when we found her, has had the heartworm treatment and now tests negative and seems to be in great shape. She seems to have these weird little seizures where she starts continuously clicking her teeth together and drooling for about 30 seconds or so then she just moves on like nothing ever happened. Does anyone know anything about this?

Thanks!