How Alcohol May Affect Human Behaviour 4. A young man started behaving in an aggressive and abusive manner after he had a number of alcoholic drinks at a party. The next day he was behaving quite normally and was quite concerned when shown a video of his behaviour the previous night. Explain how alcohol may affect human behaviour. Some Facts(1) Australian industry loses more than one billion dollars a year because of sickness caused by alcohol. Alcohol plays a part in more than 50% of serious crimes in Australia. In violent crimes it plays an even bigger part: more than 75% of them are linked to alcoh