The Jewel Wasp's parasitic manipulation of the American cockroach involves injecting venom into the cockroach's head ganglion, specifically targeting the central complex (CC) to induce increased grooming and a hypokinetic state, where spontaneous walking is significantly decreased. The wasp’s venom contains large amounts of the neurotransmitter dopamine, which activates the cockroach’s dopamine receptors, namely D1 and D2. Recent studies have shown that the D1 receptor is directly related to initializing grooming. Yet the D2 receptor’s effect on cockroach behavior is still unclear. Dopamine follows a bell-curve effect, where mean levels of dopamine yield optimal results. Bromocriptine, a dopamine agonist, primarily targets the D2 receptor. The purpose of this study was to investigate the effect of the dopamine receptor D2 on cockroach behavior, specifically grooming and walking. My hypothesis was that the D2’s effect on cockroach behavior will follow a bell-curve shape. In order to test my hypothesis, I injected bromocriptine into the central complex of 21 adult male cockroaches, divided into 4 groups of different bromocriptine concentrations (0.1M, 0.02M, 0.01M and 0.002M) and one control group. I tested the cockroaches’ grooming and walking for a duration of 30 minutes pre- and post-surgery. Then, I compared the two tests to determine how much each cockroach’s behavior changed. The research shows that the D2 receptor affects both walking and grooming in cockroaches. Walking behavior increased for every concentration tested, with the largest increase in the 0.02M concentration. Grooming behavior increased for every concentration tested too, with the largest increase in the 0.01M concentration. Largely, the cockroaches’ behavior post-surgery followed a bell-graph shape, supporting my hypothesis, however, more experiments are needed in order to completely confirm these results.