Hypokinesia is one of the classifications of movement disorders, and refers to decreased bodily movement. Hypokinesia is characterized by a partial or complete loss of muscle movement due to a disruption in the basal ganglia. Hypokinesia is a symptom of Parkinsons disease shown as muscle rigidity and an inability to produce movement. It is also associated with mental health disorders and prolonged inactivity due to illness, amongst other diseases. The other category of movement disorder is hyperkinesia that features an exaggeration of unwanted movement, such as twitching or writhing in Huntingtons disease or Tourette syndrome. Spectrum of disorders
Hypokinesia describes a variety of more specific disorders:

Causes
The most common cause of Hypokinesia is Parkinsons disease, and conditions related to Parkinsons disease. Other conditions may also cause slowness of movements. These include hypothyroidism and severe depression. These conditions need to be carefully ruled out, before a diagnosis of Parkinsonism is made. The remainder of this article describes Hypokinesia associated with Parkinsons disease, and conditions related to Parkinsons disease. Pathophysiology
Associated neurotransmitters
Dopamine
The main neurotransmitter thought to be involved in hypokinesia is dopamine. Essential to the basal ganglionic-thalamocortical loop, which processes motor function, dopamine depletion is common in these areas of hypokinesic patients. Bradykinesia is correlated with lateralized dopaminergic depletion in the substantia nigra. The dopamine pathway in the substantia nigra is essential to motor function, and commonly a lesion in this area correlates with displayed hypokinesia.
Demographic differentiation
Gender
More men than women typically develop hypokinesia, which is reflected in young and middle-aged populations where females have displayed higher levels of nigrostriatal dopamine than males. In the elderly, however, this differentiation is not present. Typically, women exhibit more tremor in the beginning development of hypokinesia. In the disorder, men tend to display more rigidity and women more bradykinesic motor behavior.Age of onset
Hypokinesia is displayed in the brain and outwardly slightly different depending on when an individual is first affected. In young-onset hypokinesia (younger than 45 years of age), typically slightly more cell loss occurs in the substantia nigra with more displayed dystonia and muscle stiffness. In old-onset hypokinesia (older than 70 years of age), typically more of a hypokinesic gait and difficulty walking and no dystonia are seen. Both onsets can display resting tremor, although more generally found in old-onset cases. Symptoms
Stress causes alterations of cerebral circulation, increasing blood flow in the supramarginal gyrus and angular gyrus of the parietal lobe, the frontal lobe, and the superior temporal gyrus of the left hemisphere. Also, an increase in cardiac activity and change in the tonus of the heart vessels occurs, which is an elementary indication of stress development. In patients with normal stress, an adaptive fight-or-flight response is usually triggered by sympathetic nervous system activation. Hypokinesia patients experience these typical stress symptoms on a regular basis because of damage to the basal ganglia system.