The continuum concept is an idea relating to human development

Human development (biology)

Human development is the process of growing to maturity. In biological terms, this entails growth from a one-celled zygote to an adult human being.- Biological development:...

 proposed by Jean Liedloff

Jean Liedloff

Jean Liedloff was an American author, born in New York, and best known for her 1975 book The Continuum Concept....

 in her 1975 book The Continuum Concept. According to Liedloff, in order to achieve optimal physical, mental and emotional development, human beings—especially babies—require the kind of experience to which their species adapted during the long process of their evolution. For infants, these include such experiences as:

• The infant being placed immediately in the mother's arms at birth, and from then on carried constantly in arms or otherwise in contact with someone, usually the mother, and allowed to observe (or nurse, or sleep) while the carrier goes about his or her business—until the infant begins creeping, then crawling on his/her own impulse, usually at six to eight months;
• Co-sleeping
  Co-sleeping
  Co-sleeping is a practice in which babies and young children sleep close to one or both parents, as opposed to in a separate room. It is standard practice in many parts of the world, and is practiced by a significant minority in countries where cribs are also used...
  
   in the parents' bed, in constant physical contact, until leaving of their own volition (often about two years);
• Breastfeeding
  Breastfeeding
  Breastfeeding is the feeding of an infant or young child with breast milk directly from female human breasts rather than from a baby bottle or other container. Babies have a sucking reflex that enables them to suck and swallow milk. It is recommended that mothers breastfeed for six months or...
  
   "on cue"—nursing in response to the child's body's signals;
• Having caregivers immediately respond to body signals (squirming, crying, etc.), without judgment, displeasure, or invalidation of the child's needs, yet showing no undue concern nor making the child the constant center of attention;
• Sensing (and fulfilling) elders' expectations that he or she is innately social and cooperative and has strong self-preservation instincts, and that he or she is welcome and worthy.

Liedloff suggests that when certain evolutionary expectations are not met as infants and toddlers, compensation for these needs will be sought, by alternate means, throughout life—resulting in many forms of mental and social disorders. Liedloff's recommendations fit in more generally with evolutionary psychology

Evolutionary psychology

Evolutionary psychology is an approach in the social and natural sciences that examines psychological traits such as memory, perception, and language from a modern evolutionary perspective. It seeks to identify which human psychological traits are evolved adaptations, that is, the functional...

, attachment theory

Attachment theory

Attachment theory describes the dynamics of long-term relationships between humans. Its most important tenet is that an infant needs to develop a relationship with at least one primary caregiver for social and emotional development to occur normally. Attachment theory is an interdisciplinary study...

, and the philosophy known as the Paleolithic lifestyle

Paleolithic lifestyle

A paleolithic lifestyle refers to living as humans did in the paleolithic era , or attempting to recreate such a lifestyle in the present day. The rationale for such an approach is that humans have evolved for millions of years in a paleolithic environment...

: optimizing well-being by living more like our hunter-gatherer

Hunter-gatherer

A hunter-gatherer or forage society is one in which most or all food is obtained from wild plants and animals, in contrast to agricultural societies which rely mainly on domesticated species. Hunting and gathering was the ancestral subsistence mode of Homo, and all modern humans were...

ancestors.