Low levels of the neurotransmitter appear to contribute to aggression. a. norepinephrine b. dopamine c. serotonin d. gaba

Low levels of the neurotransmitter serotonin may appear to contribute to aggression. Dopamine and serotonin are the most hormones that are linked with aggression, that is low level of serotonin  and high levels of dopamine. The normal effect of serotonin is the inhibitory effect on aggression levels when at normal levels. At the pre-Frontal Cortex serotonin is usually found at its lowest levelsnand increases aggression. 

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