[생물심리학] Is it possible to make human be ‘Berserker’ state?

  Do you know the Berserker? It means the brave hero in the legend of Northern Europe, who has no fear to attack. And nowadays in many on-line games it refers the blind status for attacking or aggressive states toward someone or something. Now I’d like to discuss the possibility for making human be berserker state especially by methods related to brain. And one thing that I’d like to mention before I start to discuss is I’ll purely try to figure out the ‘possibility’ only.

  In some studies there are many factors related with aggression. For instance, there are researches studying chemical substances regarding aggression like testosterone. Reinsich, Ziemba-Davis, and Sanders (1991) observed children whose mothers had been given testosterone in an effort to prevent miscarriage showed higher average physical aggression scores than their unexposed siblings of the same sex. Not only the testosterone, but the serotonin level serves the role of predicting the aggression. One reason to focus on the relationship between reduced serotonin functioning and violence is findings from animal studies that show a relationship between diminished central serotonin functioning and impaired inhibition of responses that require individuals to wait or withhold a response or risk punishment or injury. (Soubrie 1986; Higley et al. 1992; Mehlman et al. 1994)

  From the studies mentioned above, high level of testosterone and low level of serotonin might evoke someone’s aggression above the baseline. But I think chemical substances just can ‘regulate’ the aggression not ‘leave’ the aggression ‘only’. So rather than look chemical substances, I’d like to look more certain way to make human be berserker state met with the precise meaning of the berserker and it should be related to the methods which invade the brain.

  Early physiologists discovered that removal of the cerebral cortices produced violent rage of cats and dogs. John Flynn (1967) found that stimulation on cats’ medial hypothalamus made her arching a back, spitting and hissing. Amygdala is also related to the aggression. Karl Pribram and his colleagues (1954) observed a reduction in aggression when the amygdala of male rhesus monkey was removed. There is also some emerging evidence that antisocial behavior leading to violence may be associated with the impairment in the orbitofrontal cortex. (Davidson, Putnam, & Larson, 2000)

  But I think that damaging or stimulating the brain has many potential dangers because researchers might touch the unwanted brain part that might cause unexpected lesions or responses. In addition, because the function and the location or structure of the brain is not precisely one-to-one correspondence but distributed, so even if we remove a certain part of the brain, the aggression level may be not able to increase.

  There are also overall problems that most of the above studies are based on the animal research. It means that the above studies can’t apply to human identically. Of course human is biologically similar to many animals used in the studies but it doesn’t mean the same, so testosterone, serotonin or brain invading methods may not function exactly same with the animals. And basically, the above discussion only focused to the biological and physiological views. Human develop aggression not only by the mentioned methods above but by the special environmental circumstances like a war. So the possibility to make a person be berserker state by methods related to brain will be not zero but not so much high.
 
  To sum up, we have discussed the possibility of making berserker status to human with many experimental findings regarding chemical substances act in the brain and brain invading skills. In fact they have real effects which increase the aggression but have limitation that we cannot wholly control the variables. To raise the possibility, both the above experimental methods related to brain and other detail ways not related to brain directly like reinforcement schedule can be used and we should also take environmental influences in mind.