Most other tremors occurred in association with hand tremor. It has been examined for controlling essential tremor and other types of involuntary neurological tremors. Birds affected by strychnine poisoning exhibit wing droop, salivation, tremors, muscle tenseness, and convulsions. With excessive dosage, tremors, convulsions and increased body temperature are observed. Neurological disorders that may occur as complications include seizures and tremors. Uncontrolled movement such as restlessness, tremors, and muscle stiffness may occur. Central nervous system effects include ataxia, tremors, and seizures. Vaping may harm neurons and trigger tremors and spasms. Poisoning can lead to tremors and seizures. Adverse effects include weight gain, sleepiness, drooling and tremors. Parkinson's disease is characterized by severe motor problems, mainly hypokinesia, rigidity, tremors, and postural imbalance. A paralysis accompanied by involuntary tremors is usually called "palsy". Elevated blood pressure and muscle tremors are relatively common. It commonly manifests as dementia, memory problems, and parkinsonism (tremors and lack of coordination). Frequent low intensity earth tremors and occasional volcanic activity are felt throughout the islands.