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What Is The Point of Aggressive Behavior?

Amelia Jordan's picture

Aggression is an emotion that is very present in our everyday lives. Behaviors that reflect aggression can be observed in almost every aspect of the media, including television shows, movies, video games and the news; we can also observe aggressive behavior in ourselves. This type of behavior is generally exhibited in a negative manner, causing pain or unhappiness to the recipient of the aggression. If aggressive behavior results in violence and/or other detrimental outcomes, why is it that humans are capable of expressing it? What sections of the brain are involved in the modulation of aggression and is it possible that this emotion serves a positive purpose?

Neural control of aggressive behavior is hierarchical, meaning that the movements one makes when aggressively attacking or defending himself/herself are programmed by neural circuits inside the brain stem, and the brain stem is controlled by the hypothalamus and amygdala (1). The amygdala coordinates various components of emotional responses through its abundant connections to the olfactory system, hippocampus, striatum, thalamus, hypothalamus, brain stem nuclei and the prefrontal cortex (2). Emotions “begin” in the amygdala but are controlled by a particular region of the prefrontal cortex, called the orbitofrontal cortex (3). The orbitofrontal cortex receives
direct input from the dorsomedial thalamus, temporal cortex, ventral tegmental area, and of course, the amygdala. The inputs supply the orbitofrontal cortex with information on what is happening in the environment as well as the plans of the other frontal lobes. The orbitofrontal cortex is then able to create an output that affects a number of behaviors and physiological responses, including responses organized by the amygdala. The orbitofrontal cortex is ultimately responsible for translating judgments and decisions on events into appropriate behaviors and feelings. Thus, when the amygdala provokes possible aggressive actions, the orbitofrontal cortex suppresses them by forcing us to see the negative consequences. Functional imaging studies have demonstrated that anger activates the prefrontal cortex, which indicates inhibitory control over behavior. Violent criminals were shown to have low levels of activity in that region, which provides further evidence for the fact that the prefrontal cortex modulates aggression (1).

It is evident that aggression exists on a neurological level and for positive purposes related to reproduction. In order to evolve and survive, early humans had to be aggressive when defending their territory and children, and when finding a suitable mate. Reproductive aggression brings us from a hierarchical model of aggression to a form of aggression that is greatly influenced by hormones. Maternal aggression, for example, is triggered by the secretion of progesterone; intermale aggression appears to increase with a rise in testosterone levels, which occurs in their early teens, during puberty. At times, current situations may call for a mother to be protective of, but not aggressive over, her child. On the other hand, it seems rather unreasonable for a teenage boy to rely on his aggression to help him find a wife and home in this day and age. Although the human race as a whole has evolved, the hormones that caused aggression in our ancestors remain in us today. These hormones are still crucial for our development, but they needn’t be a source of aggression any longer.

Ultimately, it seems that there are no modern positive reasons for humans to engage in aggressive behavior. If aggression is employed for self-defense, it indicates that the defendant was provoked by an initial aggressive act that was presumably, unnecessary (because if the initial act was done on the assailant’s own accord, not as a reaction to an aggressive stimulus, it would be considered unnecessary). Clearly our brains have mechanisms that inhibit potential, negative behaviors, so what is the point to having the capacity for such aggression? Perhaps aggression was a biological trait given to our ancestors for survival that we are now unable to evolve past due to the manner in which we regularly and unnecessarily utilize it.

 

 

 

 

 

 

 

 

WWW Sources

1) Carson, N. (2004). Physiology of Behavior: Eighth Edition. Boston: Pearson (Allyn and Bacon).

 

 

2) Meyer, J. & Quenzer, L. (2005). Psychopharmacology: Drugs, the Brain and Behavior. Massachusetts: Sinauer Associates Inc.

 

3) http://en.wikipedia.org/wiki/anger (sorry everyone, it posted twice and I can't cut out the second post of it, because it won't let me) Aggression is an emotion that is very present in our everyday lives. Behaviors that reflect aggression can be observed in almost every aspect of the media, including television shows, movies, video games and the news; we can also observe aggressive behavior in ourselves. This type of behavior is generally exhibited in a negative manner, causing pain or unhappiness to the recipient of the aggression. If aggressive behavior results in violence and/or other detrimental outcomes, why is it that humans are capable of expressing it? What sections of the brain are involved in the modulation of aggression and is it possible that this emotion serves a positive purpose?
Neural control of aggressive behavior is hierarchical, meaning that the movements one makes when aggressively attacking or defending himself/herself are programmed by neural circuits inside the brain stem, and the brain stem is controlled by the hypothalamus and amygdala (1). The amygdala coordinates various components of emotional responses through its abundant connections to the olfactory system, hippocampus, striatum, thalamus, hypothalamus, brain stem nuclei and the prefrontal cortex (2). Emotions "begin" in the amygdala but are controlled by a particular region of the prefrontal cortex, called the orbitofrontal cortex (3). The orbitofrontal cortex receives direct input from the dorsomedial thalamus, temporal cortex, ventral tegmental area, and of course, the amygdala. The inputs supply the orbitofrontal cortex with information on
what is happening in the environment as well as the plans of the other frontal lobes. The orbitofrontal cortex is then able to create an output that affects a number of behaviors and physiological responses, including responses organized by the amygdala. The orbitofrontal cortex is ultimately responsible for translating judgments and decisions on events into appropriate behaviors and feelings. Thus, when the amygdala provokes possible aggressive actions, the orbitofrontal cortex suppresses them by forcing us to see the negative consequences. Functional imaging studies have demonstrated that anger activates the prefrontal cortex, which indicates inhibitory control over behavior. Violent criminals were shown to have low levels of activity in that region, which provides further evidence for the fact that the prefrontal cortex modulates aggression (1).
It is evident that aggression exists on a neurological level and for positive purposes related to reproduction. In order to evolve and survive, early humans had to be aggressive when defending their territory and children, and when finding a suitable mate.
Reproductive aggression brings us from a hierarchical model of aggression to a form of aggression that is greatly influenced by hormones. Maternal aggression, for example, is triggered by the secretion of progesterone; intermale aggression appears to increase with
a rise in testosterone levels, which occurs in their early teens, during puberty. At times current situations may call for a mother to be protective of, but not aggressive over, her child. On the other hand, it seems rather unreasonable for a teenage boy to rely on his aggression to help him find a wife and home in this day and age. Although the human race as a whole has evolved, the hormones that caused aggression in our ancestors remain in us today. These hormones are still crucial for our development, but they needn't be a source of aggression any longer.
Ultimately, it seems that there are no modern positive reasons for humans to engage in aggressive behavior. If aggression is employed for self-defense, it indicates that the defendant was provoked by an initial aggressive act that was presumably, unnecessary (because if the initial act was done on the assailant's own accord, not as a reaction to an aggressive stimulus, it would be considered unnecessary). Clearly our brains have mechanisms that inhibit potential, negative behaviors, so what is the point to having the capacity for such aggression? Perhaps aggression was a biological trait given to our ancestors for survival that we are now unable to evolve past due to the manner in which we regularly and unnecessarily utilize it.

 

 

 


WWW Sources
1) Carson, N. (2004). Physiology of Behavior: Eighth Edition. Boston: Pearson (Allyn and Bacon).


2) Meyer, J. & Quenzer, L. (2005). Psychopharmacology: Drugs, the Brain and Behavior. Massachusetts: Sinauer Associates Inc.

3) http://en.wikipedia.org/wiki/anger