Final answer:
The question pertains to brain lesions that might cause a change in personality, implicating damage to the prefrontal cortex, which controls executive functions and behavior inhibition. Historical precedent shows that such injuries can lead to significant personality shifts, but also that the brain has a remarkable ability to adapt and recover from trauma.
Step-by-step explanation:
The subject of the question relates to a location of lesion in the brain that correlates with personality changes. When a previously pleasant person becomes profane and irresponsible, one can assume that there might be damage to the frontal lobes, particularly the prefrontal cortex, which is responsible for executive functions and inhibiting inappropriate behavior. In famous historical medical cases, such as Phineas Gage, injuries to this area led to significant personality changes. The description suggests that altered behavior post-trauma is not uncommon, and while some of this behavior might be influenced by other factors like the use of alcohol for pain relief, the injury to the brain clearly plays a central role. Importantly, the capacity for the brain to adapt and exhibit neuroplasticity, allowing for recovery of certain functions and return to work, for example, as a stagecoach driver, is also recognized.