Hemianesthesia to sensory and stereognostic stimuli with decreased or absent perception of body position and passive movement; also with variable hemiplegia, hemiparesis and dysarthria. Application of cold can cause jerky motor action. Cause is lesion in thalamus (lesion involving nucleus ventralis posterolateralis or thrombosis of thalamogeniculate artery) contralateral to affected side; cause is very rarely white matter lesion in contralateral parietal lobe.