ABSTRACT
The questions of which basic psychological needs must be met in order to attain mental health and well-being, and how these basic needs influence human behavior, have been answered very differently from various theoretical perspectives. Basic psychological needs are needs that are present among all humans, and their violation or enduring nonfulfillment leads to impairments in mental health and well-being. The chapter provides an overview of the most important constructs of consistency theory and of their interrelationships. It discusses the relation between basic needs and consistency regulation in mental/neural functioning. The chapter examines the way in which they influence a person’s experience and behavior. Discordance and incongruence represent two particularly important forms of inconsistency in mental functioning. Inconsistency is a state that an organism strives hard to avoid. The human mental system has formed all kinds of mechanisms to avoid or remove inconsistency.
