The Aggression Systems
Evolution of Aggression - Introduction Page 13

Table of Contents


Preface Pages 1 - 2


Human aggression - introduction Pages 3 - 4 - 5 - 6 - 7 - 8


Evolution of aggression - introduction Pages  9 - 10 - 11 - 12 - 13 - 14


Brain mechanisms of aggression - introduction Pages 15 - 16 - 17 - 18 - 19 - 20


Dynamics of aggression - introduction Pages 21 - 22 - 23


The shift of motivating stimuli from olfaction to vision makes possible the development of complex social structures that characterize primates and are absent in rodents. As pointed out, the time course of olfactory recognition is so slow that when a stranger is placed in the midst of a group of rodents, they attack not only the stranger but each other as well. The visual discrimination of individuals by primates takes place almost instantly and enables them to develop coalition and other complex social relationships within rapidly occurring behavior sequences.

To some extent, the offense behavior of humans continues to be similar to the offense of primates. Consistent with the general law proposed above, the central portion of the system probably remains the same. Humans, when angry, probably have activity of the same brain cells in the offense motivational mechanism, as do primates and rats. It is the sensory and motor sides that have changed dramatically. One sensory aspect may remain similar, however: the competitive fighting analyzer. Humans also can fight over food when hungry. In humans the operation of this sensory analyzer may have been further developed to mediate the frustration-induced anger corresponding to other motivations as well. And on the motor side, the motor patterns of offense in the monkey are retained in humans, including approach, hitting, and rough restraint. Biting may also occur in humans, although it is socially discouraged and therefore more common in children than in adults.

Humans, of course, have expanded the repertoire of motor patterns of offense to include words and use of instruments to attack. We have become masters of verbal aggression, such as "biting words," and an angry person can be dangerous if they use weapons to inflict injury.

Most human anger is in reaction to perceived injustice. This fact, as discussed earlier on the basis of the work of Averill, indicates that there has been a radical evolutionary transformation in humans. As described in the first paper of this section, the transformation came about in three stages, beginning at the level of the non-human primates.

The first stage of the offense transformation was in the nature of the motivating stimuli. Instead of becoming angry at the attributes of the opponent (pheromones, etc) , the monkey or person can now get angry at the actions of the opponent. To some extent this already occurs in many animals during competitive fighting, but in monkeys it becomes possible to get angry in response to a much broader range of actions by others.

(Continued on next page)

previous page
home page
next page