Symptoms and signs: Nervous system

Myotonia (Myo from Greek; muscle, and Tonus from Latin; tension) is a symptom of a small handful of certain neuromuscular disorders characterized by delayed relaxation (prolonged contraction) of the skeletal muscles after voluntary contraction or electrical stimulation.

Hemispatial neglect, also called hemiagnosia, hemineglect, unilateral neglect, spatial neglect, contralateral neglect, unilateral visual inattention, hemi-inattention, neglect syndrome or contralateral hemispatialagnosia is a neuropsychological condition in which, after damage to one hemisphere of the brain is sustained, a deficit in attention to and awareness of one side of space is observed.

Abnormal posturing is an involuntary flexion or extension of the arms and legs, indicating severe brain injury.

Meningism is the triad of nuchal rigidity (neck stiffness), photophobia (intolerance of bright light) and headache.

Athetosis is a symptom characterized by slow, involuntary, convoluted, writhing movements of the fingers, hands, toes, and feet and in some cases, arms, legs, neck and tongue.

Agnosia is the inability to process sensory information.

Akathisia is a movement disorder characterized by a feeling of inner restlessness and a compelling need to be in constant motion, as well as by actions such as rocking while standing or sitting, lifting the feet as if marching on the spot, and crossing and uncrossing the legs while sitting.

Cataplexy is a sudden and transient episode of muscle weakness accompanied by full conscious awareness, typically triggered by emotions such as laughing, crying, or terror.

Dysarthria is a motor speech disorder resulting from neurological injury of the motor component of the motor-speech system and is characterized by poor articulation of phonemes (cf. aphasia: a disorder of the content of language).

Neuralgia (Greek neuron, "nerve" + algos, "pain") is pain in the distribution of a nerve or nerves, as in intercostal neuralgia, trigeminal neuralgia, and glossopharyngeal neuralgia.

Radial neuropathy (or radial mononeuropathy) is a type of mononeuropathy which results from acute trauma to the radial nerve that extends the length of the arm.

Airsickness is a sensation which is induced by air travel.

Clouding of consciousness, also known as brain fog or mental fog, is a term used in medicine denoting an abnormality in the regulation of the overall level of consciousness that is mild and less severe than a delirium.

Dyskinesia refers to a category of movement disorders that are characterized by involuntary muscle movements, including movements similar to tics or chorea and diminished voluntary movements.

Asterixis (also called the flapping tremor, or liver flap) is a tremor of the hand when the wrist is extended, sometimes said to resemble a bird flapping its wings.

The straight leg raise, also called Lasègue's sign, Lasègue test or Lazarević's sign, is a test done during the physical examination to determine whether a patient with low back pain has an underlying herniated disk, often located at L5 (fifth lumbar spinal nerve).

Hemiparesis is unilateral paresis, that is, weakness of the entire left or right side of the body (hemi- means "half").

Ballismus or ballism (called hemiballismus or hemiballism in its unilateral form) is a very rare movement disorder.

Allochiria (from the Greek meaning "other hand") is a neurological disorder in which the patient responds to stimuli presented to one side of their body as if the stimuli had been presented at the opposite side.

Hypertonia is a term sometimes used synonymously with spasticity in the literature surrounding damage to the central nervous system, namely upper motor neuron lesions.

A convulsion is a medical condition where body muscles contract and relax rapidly and repeatedly, resulting in an uncontrolled shaking of the body.

Dyschronometria is a condition of cerebellar dysfunction in which an individual cannot accurately estimate the amount of time that has passed (i.e., distorted time perception).

Alachryma is a disease of the autonomic nervous system where there is a lack of tear production.

Coprographia is involuntarily making vulgar writings or drawings.

Dysmetria (English: wrong length) refers to a lack of coordination of movement typified by the undershoot or overshoot of intended position with the hand, arm, leg, or eye.