The critical period concept: Research, methodology, and theoretical issues.

Abstract

The concept of "critical periods" in postnatal behavioral development is reviewed. Evidence on the criteria and characteristics of critical period phenomena is considered with respect to endogenous and exogenous influences; methodology of critical period research is described and evaluated; and conceptual issues and problems are discussed in light of past attempts at subclassification of the field and recovery of function as a refutation of the critical period hypothesis. It is concluded that the critical period concept is viable if certain limitations are observed.

Judgments of information structure in L2 French: Nativelike performance and the Critical Period Hypothesis

“…Typically, there is an abrupt onset or increase of sensitivity, a plateau of peak sensitivity, followed by a gradual offset or decline, with subsequent flattening of the degree of sensitivity" (Birdsong 2005: 111; see also Bornstein 1989, Colombo 1982. Under this definition, a critical period starts at the peak level of sensitivity and includes any decline and subsequent reduced level of sensitivity that follows.…”

The influence of prenatal tactile and vestibular stimulation on auditory and visual responsiveness in bobwhite quail: A matter of timing

“…For example, findings from research assessing the effects of exposure to alcohol and maternal stress during early development have indicated that when exposure to these events occurs during prenatal development can have a significant impact on subsequent outcomes (Martin, Noyes, & Wisenbaker, 1999;Mattson, Schoenfield, & Riley, 2001;Schneider, Roughton, Koehler, & Lubach, 1999). Although the concept of a sensitive or critical period generally refers to the idea that particular experiences can influence developmental outcomes more at one time during ontogeny than at other times (see Bateson, 1979;Columbo, 1982), we are pointing to a more pervasive influence of timing on development, one in which timing is a fundamental aspect of the role of experience in individual ontogeny. Because the notion of timing deals with relationships (rather than individual, isolated entities and events), empirical efforts must take into account the nested set of relationships within which a particular system under investigation is embedded.…”

Psycho-Ecological Systems Model: A Systems Approach to Planning and Gauging the Community Impact of Community-Engaged Scholarship

“…Each developmental period (infancy, early childhood, elementary school age, adolescence, adulthood, old age) consists of a distinctive set of abilities, limitations, demands, and tasks (Kiesler, 2000), which (a) make a person more or less sensitive to certain environmental factors, (b) influence the person's vulnerability or resiliency in the face of a particular negative event, and (c) determine one's level of readiness to benefit from particular types of experience. For instance, within a critical period (see classic article by Colombo, 1982), there is an intensified sensitivity to particular stimuli in the environment. Normal development in some domains (e.g., language acquisition) depend upon exposure to certain stimuli (e.g., language) during a critical period (see classic work by Lenneberg, 1967).…”