Using a battery of imaging and cognitive tests, Johns Hopkins specialists have gathered evidence of accumulated brain damage that may be linked to specific memory deficits experienced by former National Football League players decades after retirement.  Although the healthy controls were observed to have no evidence of brain damage, PET scans revealed the former NFL players had evidence of brain injury in several regions of the temporal medial lobe, including the amygdala, which plays a significant role in regulating mood, according to the release. {read more here}