Aggression is defined as any sequence of behavior used by a person

Aggression is defined as any sequence of behavior used by a person with an intension or purpose to harm another person either physically or mentally. The main theoretical perspectives on aggression are: social learning theory, frustration aggression hypothesis and instinct theory of aggression. Aggression serves an important function in terms of individual survival, defense during games and reproductive potential. Lorenz’s theory on animal nature suggests that aggression as an innate, is a response triggered by environmental or external stimuli. Lorenz (1935) refers innate behaviours to perceptual patterns which occur for the first time when the proper stimuli are present. Lorenz and Tinbergen (1942) by “innate” behavior, mean behaviour which is hereditarily determined from part of the original constitution of an animal, which arises quite independently of the animal’s experience and environment and which is distinct from acquired or learned behaviour. Lorenz suggested that innate behaviour is noticeable in animals which have been raised in isolation from others and it develop fully-formed in animals which have been prevented from practicing it, such as pecking in the chicks, domestic chicks characteristically begin to peck at objects soon after hatching (Bird, 1913). Pecking behaviour is ordinarily coordinated into a single resultant act of lunging the grain while opening the bill and swallowing. This coordination is present soon after hatching and improves later even if the chick is prevented from practicing. This picking is stereotyped, characteristic of species, appear in isolated chicks. So, Lorenz relates this theory to humans. Michael suffers from a chromosomal anomaly, this means his aggressive behaviors are “innate” according to Lorenz’s theories. The additional chromosome caused him to have learning difficulties and poor concentration during his childhood at school. Berkowitz (1965) argued that frustration does not always directly trigger aggression, but every frustration creates an instigation to aggression. Berkowitz (1987) believes that it is important to draw the distinction of aggression into two: instrumental aggression – primarily used toward the attainment of some other objective like self-defense, territory, social status or money, and hostile aggression – the primary goal is to hurt. Berkowitz (1974) suggested that aggression cues may function as discriminative stimuli. The cues may signal to an individual that acting aggressively will provide reinforcement. Berkowitz and Geen (1967) argued that frustration-engendered aggression can become manifest when restraints against are lowered or the aggressive response tendency is heightened. They carried out an experiment where they asked subjects to complete a puzzle after watching a violent and nonviolent film, the results in the experiment showed that subjects after watching a violent film were more punitive towards an innocent target than subjects who watched a nonviolent one. Bandura (1925 – present) observed that aggression behaviour can be learned by observing or imitating the aggressive behaviour from others. His Social Learning Theory (SLT) emphasises on the important internal process that occurs in the individual’s brain. He believes that aggressive behaviours to be learned from the environment is caused by observational leaning and mediating processes that occur between stimuli and responses. The theory is illustrated through his famous Bobo Doll Experiment (Bandura, 1961). The experiment was conducted on different groups of children (boys and girls) from a nursery school. The first group watched a female or a male model displaying aggressive behaviour of abusing the bobo doll in both verbally and physically, hitting with hammer and shouting like hit him. The second group also watched a model playing quietly with the bobo doll in non-aggressive manner. The results showed that the first group imitated with aggressive responses to the bobo doll in comparison to the second group. Bandura replicated the experiment in 1965 as a result of measuring vicarious reinforcement in similar setup. Both groups watched the aggressive models. The first group saw the model’s aggression being rewarded with sweets whereas in the second group the model was scolded for the aggressive behavior towards a bobo doll. As a result, the second group observed the aggressive behaviour but did not imitate them because of the expected negative consequences, whilst, the first group responded with aggressive actions with expectations for rewards. Social learning theory explains Michael’s increasing violence when attended Pupil Referral Unit. Heat affects aggressive thoughts according to Rule, Taylor, and Dobbs (1987). They have examined the effects of hot temperatures on a cognitive state variable. Experiments were conducted on two different groups of participants. The groups were asked to complete aggression-relevant story stems and aggression-irrelevant story stems under normal and hot- temperature conditions. The results showed that participants who completed aggression-relevant story stems in hot-temperature conditions used more negative elements than participants in the normal-temperature condition. Whereas, when completing neutral context (aggression-irrelevant) story stems, there was no significant difference between participants in the two different temperature conditions. In conclusion, Michael inherited aggressive behaviours were as a result of chromosomal abnormalities. His aggression is typed as hostile aggression because he caused harm to other children at school. The continuous violence and aggression might have developed through observational leaning and mediating processes from the aggressive environment he stayed in at home and pupil referral unit as he was growing up according to Bandura learning theories.