Occurrence Of Abnormal Movements Research Articles

Drug-Induced Movement Disorders.

Drug-induced movement disorders (DIMDs) are most commonly associated with typical and atypical antipsychotics. However, other drugs such as antidepressants, antihistamines, antiepileptics, antiarrhythmics, and gastrointestinal drugs can also cause abnormal involuntary movements. Different types of movement disorders can also occur because of adverse drug reactions. Therefore, the important key to diagnosing DIMDs is a causal relationship between potential offending drugs and the occurrence of abnormal movements. The pathophysiology of DIMDs is not clearly understood; however, many cases of DIMDs are thought to exert adverse mechanisms of action in the basal ganglia. The treatment of some DIMDs is quite challenging, and removing the offending drugs may not be possible in some conditions such as withdrawing antipsychotics in the patient with partially or uncontrollable neuropsychiatric conditions. Future research is needed to understand the mechanism of DIMDs and the development of drugs with better side-effect profiles. This article reviews the phenomenology, diagnostic criteria, pathophysiology, and management of DIMDs.

Index of Suspicion in the Nursery

A 2-month-old male baby is admitted to the hospital for the third time with a history of abnormal movements since the first day after delivery. He returns to the hospital on this occasion due to the appearance of bluish skin associated with the occurrence of abnormal movements that persist despite the use of anticonvulsant medication. The parents describe the abnormal movement as a sudden, startling jump followed by a forceful body contraction in which the baby becomes rigid, with fists firmly clenched, arms flexed, spine erect, head tilted slightly backward, and legs extended. He remains awake during and after the episode. The contraction lasts for approximately 10 seconds and is followed by floppiness for 1 to 2 seconds. Sometimes episodes are accompanied by a bluish coloration of the entire body. Startling sounds or even a sudden touch trigger the episodes, which occur frequently all day long. They explain that firm holding and hugging sometimes seem to stop the episodes. On questioning, they report no eye rolling, blinking, or lip smacking during the episodes, and the episodes usually are not preceded by feedings. The boy has good suckling and appetite; no constipation or diarrhea; and is active, afebrile, and seemingly otherwise healthy. A review of the pregnancy and delivery reveals no complications or infections during the pregnancy, although the mother says that the movements of the baby in the womb seemed different from those in …

Ictal movement disorders and hypothalamic hamartoma

We report the case of a woman presenting with unusual, symptomatic epilepsy related to a hypothalamic hamartoma, in the absence of mental retardation or precocious puberty. The seizures manifested themselves clinically as characteristic, paroxysmal movement disorders, such as choreic/ballistic movement. This type of phenomenon is rarely of epileptic origin: we thus suggest that the movement disorder observed here could be due to functional disorganization of the basal ganglia network by the epileptic discharge, causing loss of the inhibition of thalamic activity and thus allowing the occurrence of abnormal movements. [Published with videosequences]

Behavioral Consequences of Bicuculline Injection in the Subthalamic Nucleus and the Zona Incerta in Rat

The subthalamic nucleus (STN) plays a crucial role in basal ganglia functions and has been shown to be hyperactive in parkinsonian syndromes. The zona incerta (ZI), located dorsally to the STN, is also reported to be overactive after nigrostriatal denervation. In this study, we examined the behavioral consequences of an increased activity of the STN or the ZI in awake, freely moving rats. Unilateral microinjections of a GABA(A) receptor antagonist (bicuculline; 25, 50, and 100 microg/microl) were performed in the STN or in the ZI of rats, and locomotor activity, spontaneous behaviors, and the occurrence of abnormal movements were quantified. Microinjection of bicuculline (50 and 100 microg/microl) into the STN did not modify spontaneous locomotor activity, whereas it induced an increase in locomotion when injected into the ZI. Furthermore, when injected into the STN or ZI, these same doses of bicuculline produced changes in spontaneous behaviors (sniffing and grooming decreased whereas chewing and rearing increased) and the appearance of abnormal movements directed contralaterally to the injection side. Application of a lower dose of bicuculline (25 ng/microl) in the STN or ZI did not modify behavior. This study suggests that the subthalamic region including the ZI, and not the STN per se, might be involved in the induction of abnormal movements. In addition, these data suggest that the hyperactivity of neurons in this region may have different consequences in the normal state and in the pathological state.

Motor/vocal tics and compulsive behaviors on stimulant drugs: Is there a common vulnerability?

The occurrence of abnormal movements or perseverative/compulsive behaviors was noted in 34 (76%) of a group of 45 hyperactive boys during a double-blind crossover treatment trial of methylphenidate and dextroamphetamine given in a wide range of doses. These adverse effects were often subtle and transient, and they usually occurred only on one drug. There was only one case where treatment was discontinued due to the severity of the tic the subject developed during his initial treatment phase. Dextroamphetamine tended to produce more compulsive behaviors, which were also more likely to resemble clinical obsessive-compulsive disorder (OCD), than did methylphenidate. Abnormal movements and compulsive behaviors tended to co-occur on methylphenidate only; no general “Tourette-OCD diathesis” was found for this population.