an iron rod when through Phineas gages face and through the top of his head damaging his prefrontal cortex
Phineas gages personality had a fundamental change he went from being a reliable person to someone who was irresponsible, profound and aggressive
case studies of people who had suffered brain damage allowed physicians to begin to map the brain
the prefrontal cortex is associated with personality and decision making and is the front area of the brain just behind the forehead
Roger Sperry (1970s)
tested humans with their corpus callosum severed as treatment for epilepsy, a seizure disorder. He found that the hemispheres in human brains had different functions. The left hemisphere interpreted language but not the right hemisphere
broca's area is located in the frontal lobe and is responsible for speech production
Paul Broca had a patient known as 'tan' through which he discovered the area of tans brain the had been damaged was responsible for motor control involved in speech production
Broca's area location
lower part of the left frontal lobe
Broca's areas function
motor control involved in speech production
Wernicke's area location
rear of the left temporal lobe as it joins to the parietal lobe
Wernicke's area function
understanding of speech
the midbrain contains an area called the periaqueductal grey matter (PAG) which links the amygdala and the hippocampus with the prefrontal cortex
the midbrain has a role in coordinating and integrating behavioral responses to perceived internal and external stressors such as pain or threat
Lonstein and Stern (1998)
lesions to the PAG in rats that have recently given birth show an increase in aggression when the rats are confronted with potential threat in the form of unfamiliar male rats being put in the cage
the amygdala is the center for emotions, emotional behavior and motivation
the amygdala integrates internal and external stimuli and every sensory modality has an input, which when combined gives us an instinctive feeling or reaction to the environment that will include aggression
the prefrontal cortex connects to the amygdala which may be the cause for the expression aggression
the hypothalamus maintains homeostasis through the regulation of hormones including hormones that regulate sexual function. this is linked to aggressive behaviour in males through the production of testosterone
lesions
damage to the brain causing the area to die
medial
middle
dorsal
back
lateral
side
homeostasis
process that maintains the stability of the human body in response to changes in external conditions like temperature
hormones are chemicals produced by glands that are used to signal between organs and tissues
testosterone is the is principle male sex hormone and an anabolic steroid
periaqueductal grey matter (PAG)
are of grey matter in the midbrain that plays a role in the modulation of pain and in defensive behaviour
prefrontal cortex location
right behind the forehead
prefrontal cortex function
it is influential in governing social interaction and regulation of behaviour
damage to the prefrontal cortex often leads to problems with anger management, irritability and impulse control