Focal neurologic signs, also known as focal neurological deficits or focal CNS signs, are impairments of nerve, spinal cord, or brain function that affects a specific region of the body, e.g. weakness in the left arm, the right leg, paresis, or plegia.
[citation needed] Focal neurological deficits may be caused by a variety of medical conditions such as head trauma,[1] tumors or stroke; or by various diseases such as meningitis or encephalitis or as a side effect of certain medications such as those used in anesthesia.
[3] Frontal lobe signs usually involve the motor system and may include many special types of deficit, depending on which part of the frontal lobe is affected:[citation needed] Parietal lobe signs usually involve somatic sensation, and may include:[citation needed] Temporal lobe signs usually involve auditory sensation and memory, and may include:[citation needed] Occipital lobe signs usually involve visual sensation, and may include:[citation needed] Damage to the limbic system involves loss or damage to memory, and may include:[citation needed] Cerebellar signs usually involve balance and coordination, and may include:[citation needed] Brainstem signs can involve a host of specific sensory and motor abnormalities, depending on which fiber tracts and cranial nerve nuclei are affected.
[citation needed] Spinal cord signs generally involve unilateral paralysis with contralateral loss of pain sensation.
[3] Other soft signs including clumsiness, and loss of fine motor movement are also commonly found in schizophrenia.