Abstract: A bearing assembly includes a lubricated bearing and a thermistor mounted in or adjacent the lubricant flow path through to or from the bearing. The thermistor is in heat exchange relationship with the lubricant and is connected in an electrical circuit so as to operate in the self heating mode to respond to a deleterious change in the flow of lubricant along the path. The rate of flow of lubricant determines the rate of dispersion of heat from the thermistor and thereby determines the temperature of the thermistor.