Chapter 9: Critical & Sensitive Periods in Development Flashcards
What is a critical period?
Critical periods in development are times of special sensitivity to certain environmental factors that can shape the individuals capacity for future development.
What are teratogens?
Toxic substances that are capable of harming an unborn child. They will affect the unborn child’s development if the child is exposed to them at specific times in their development. These effects can be tragic and cause birth defects.
What is an imprint/imprinting?
Imprinting has to do with a time within a particular species’ lifespan in which the animal is pre-programmed to learn something.
Eg. Konrad Lorenz studied how young birds imprint (form an immediate attachment), to the first moving object they see after they hatch from the egg. In most cases it is likely to be the chicks parent.
Lorenz found that the greylag goose hatchlings had imprinted on him and followed him wherever he went. They though he was their parent.
What is a sensitive period?
The best or optimal times for psychological development in certain areas, such as learning to speak in the first years of life. These periods coincide with the times when our brain’s nervous system is undergoing rapid growth.
What is experience-expectant learning?
Occurs during sensitive periods and refers to experiences necessary for learning to occur, playing an important role in the developmental organisation of the nervous system.
What is experience-dependent learning?
A form of learning that can occur at any time during an individuals life. It refers to adaptive plasticity, encoding new experiences that occur throughout life, fostering new brain growth and refining existing brain structures.
What is maturation?
An infants body and motor skills develop rapidly due to maturation, a genetically programmed process that governs growth. It directs physical and biological development including the development of an infants muscles and brain. Eg. Walking, rolling over, talking.
What are inborn reflexes?
Automatic responses to specific stimuli.
They are not learned behaviors, or a product of the environment as they do not rely on experience or the development of cognitive skills.
They are entirely due to nature (heredity.)
What are developmental norms?
An indication of the average age that a certain behaviour or skill will be achieved.
They provide feedback on whether the infant is progressing normally in relation to the rest of the population.
What is maturation and how does it differ from learning? How do they work together?
Maturation is a genetically programmed process that governs growth, where learning can be defined as a relatively permanent change in behaviour due to experience.
The two work together however, babies cannot LEARN skills such as walking until their brains and bodies are physically ready or MATURE to carry them out.
Why does the development of motor skills in infants encourage cognitive, social, and emotional development?
Motor skill milestones such as reaching out for a toy, link hand-eye coordination skills with perceptual abilities. Movement such as crawling, stimulates cognitive and social engagement.
Being able to crawl means that infants are able to investigate their surroundings and play near others.
Motor skill milestones are easily observable and demonstrate how maturation impacts psychological development.
Why are developmental norms useful? What are their limitations?
Developmental norms can be useful as they can alert health professionals to a situation and allow appropriate appropriate action.
However, they are based on the mean age of a large sample. This can cause unnecessary anxiety because the mean score doesn’t take into account the large variation within the population. An infant who takes longer to reach one milestone may be identified as being ‘at risk’, although they are perfectly healthy and normal.
How do teratogens relate to critical periods of development? Give an example.
Teratogens will affect an unborn child’s development if the unborn child is exposed to them at specific or critical period in their development. Their effects can be tragic and cause serious life long consequences, as seen for example, in the case of rubella.
Give an example of a critical period in human development.
The development of vision; human babies must receive exposure to light in the first few days of life so that the sensory neurons in the retina develop. If this fails to happen, the baby may be permanently visually impaired.
Give an example of a critical period in a non-human species.
If a chaffinch does not hear an adult singing before it sexually matures, it will never be able to sing the highly intricate song required to attract a mate.
