Final answer:
Alcohol initially affects judgment, causing a decrease in reaction time and behavioral control. Excessive consumption also significantly impairs coordination, leading to serious consequences including increased accident risks and social and physiological disorders.
Step-by-step explanation:
One of the first things affected by alcohol is judgement. When a person consumes alcohol, it has an immediate impact on the brain which leads to a decrease in reaction time, visual acuity, and behavioral control. This decrease often manifests as impaired judgement well before more noticeable physical symptoms such as loss of coordination or slurred speech occur. This is crucial because it implies that a person's ability to make sound decisions and evaluate risks accurately can be compromised well before they may appear visibly intoxicated.
The acute administration of alcohol is also associated with feelings of euphoria or sedation, depending on the dose. However, with excessive consumption, coordination can be affected as well, which is one of the reasons why activities like operating a vehicle are dangerous and illegal while under the influence. The Field Sobriety Test (FST), which assesses a driver's coordination, is a practical demonstration of how even modest amounts of alcohol can disrupt the fine motor skills needed for safe driving.
Alcohol's effects on the brain don't end with judgement and coordination. Excessive and chronic alcohol consumption has many other serious consequences including physiological disorders such as cirrhosis of the liver, and it increases the risk of certain cancers. It also poses serious threats to social well-being, such as loss of employment and family disruption, as well as to public safety highlighted by the high percentage of road accidents related to alcohol consumption.