Vygotsky's social account of psychology is comprehensible when viewed in relation to his political views and his early work experience. A brief discussion of this context is therefore in order before explaining the details of his psychological stand- point.
1 Central cyanosis and its causes are all associated with peripheral cyanosis. 2  Decreased pumping of blood by the heart or reduced cardiac output. 3  This is seen in heart failure or circulatory shock. 4  Diseases of circulation like thrombosis or embolism. 5  Constriction of blood vessels of the limbs, fingers and toes.
1 Cyanosis is seen in the tongue and lips and is due to desaturation of central arterial blood resulting from cardiac and respiratory disorders associated with shunting of deoxygenated venous blood into the systemic circulation.