Question

What is meant by the term, “critical period” as it refers to development?    Discuss how the concept of critical periods applies to various aspects of physical, brain, and perceptual development. In terms of brain development, how have research findings on neuroplasticity changed our views about the rigidity imposed by critical periods?

Answer 1

Critical period is the developmental period during an organism's life span in which the nervous system is sensitive to environmental stimuli. This period is that maturational stage during an organism's life.

It's been known to everyone that childhood experiences have the power to alter the brain development. For ex- language development is wholly dependent on hearing and if the hearing loss is not diagnosed in the early stages then the brain may not be able to receive the sound which may result into close up of language related parts in the brain. Thus restricting the development of language in a child. Same with the case of vision development, if a child is not exposed to light and other visual stimuli, then the brain areas for sight development may not develop properly.

If the child is depreived of physical and food stimulation in the early years of life, let's say the first trimester of pregnancy is the critical period of development, including the formation of tissues, organs, and cell differentiation. Exposure to harmful environmental stimuli such as teratogens( alcohol, drugs, smoking, etc) can hamper a child's physical as well as mental development.

Perceptions are shaped since early childhood. Inadequate exposure to social and psychological situation in the early six months of the child development can result into distorted sense of perception such as child who is not given appropriate warmth and nurturance may develop a more negative perception of society and people around him/her, resulting into avoiding and neglecting people and moral rules of the society.

Neuroplasticity is the ability of the brain to reorganise itseld by forming new neutral connections, thus it is a term referring to the changes in the neural structure resulting from the interactions with the environment. In the critical period of early years, the nervous system must receive some sensory inputs from the environment to develop these connections properly. Researches has shown us that children born with hearing loss are more likely to vocalise less than children with no deafness. Providing an adequate environment for such children such as using signs, symbols, and other aids results into strengthening of neural connections relating to recognition of visual information( sign language) making them able to interact and communicate effectively.