Finally, it should be noted that poor regulatory abilities, similar to those exhibited by children diagnosed with attention deficit hyperactivity disorder (ADHD), can be the result of a hormonal imbalance (Biederman et al., 1995; Conners, 1997). Often, it is ineffective to simply discipline a child for his or her aggressive, overly active behavior. Experimental research conducted by The National Institute of Mental Health found that the combination of medication and behavioral treatments is more effective in improving these behaviors than just medication or just behavior treatment (National Institute of Mental Health, 1999). Further, the study found that in certain cases, where medication or behavior therapy alone yielded little to no improvement in behavior, the combination of behavioral therapy and medication lead to behavioral improvements.