Prolonged separation of the offspring from the father.

The state of being deprived of sleep under experimental conditions, due to life events, or from a wide variety of pathophysiologic causes such as medication effect, chronic illness, psychiatric illness, or sleep disorder.

The absence or restriction of the usual external sensory stimuli to which the individual responds.

The withholding of water in a structured experimental situation.

The withholding of food in a structured experimental situation.

The absence of appropriate stimuli in the physical or social environment which are necessary for the emotional, social, and intellectual development of the individual.