Identifying Key Neurotransmitter in Hyperactivity Disorders

Neurotransmitters are fundamental chemicals in the brain that facilitate communication between neurons. Each neurotransmitter has distinct effects on behavior and physiology. Dopamine, for instance, is well-known for its role in reward and pleasure, while serotonin is often linked to mood regulation. The implications of neurotransmitter imbalances are profound, impacting psychological conditions such as depression and schizophrenia.

Consider the following scenario: A researcher is investigating a disorder characterized by excessive excitatory neurotransmitter activity leading to hyperactivity and impulsive behaviors. This research primarily focuses on identifying the predominant neurotransmitter involved in such a disorder. Given this context, which neurotransmitter might the researcher be primarily concerned with?