Psychology of Parenting
Brain Development and Childhood Learning: Critical Period

Brain Development and Childhood Learning: Critical Period

Discover what a key phase in brain development is and how parents may utilize this information to encourage optimal brain growth in their children.

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What is Critical Period

A crucial period is a period in which brain cell connections are more flexible and sensitive to the effect of a certain type of life experience. During this time, these connections, known as synapses, can develop or strengthen more easily. After this period of time, synaptic connections generally develop and alterations solidify, and wirings become more difficult to modify.

Critical Period Hypothesis

According to the Critical Period Hypothesis, during the critical period, a new skill or trait can be formed given the proper life experience. If the necessary experience is not available during this time, it becomes much harder, less successful or even impossible to acquire the skill or trait after the window of opportunity closes.

This is proven true in sensory systems in human and animals, such as vision and hearing.

For example, if one eye (but not both) is covered right after birth, the deprived eye will lose visual acuity permanently, even if the covered period is brief postnatal. This is because covering an eye during the critical period can alter the physical pathways of the brain p

Critical Period vs Sensitive Period

A sensitive phase, like a critical period, occurs when the brain is comparatively more malleable and susceptible to the effect of experience on the formation of new synapses. Despite being more challenging, new synapses can develop for a lengthy amount of time outside of this optimum timeframe.

This is referred to by some scientists as a weak critical phase.

Why Is Critical Period Important

Critical periods are significant because many critical functions of our bodies are established during those times, and some only during those times.

According to research, the following functions are best developed during their crucial times.

Emotional Regulation

The ability to monitor and control emotions is referred to as emotional self-regulation. Learning to self-regulate is an important developmental milestone for a kid. It has the potential to have a substantial influence on a childrens relationships, academic performance, mental health, and long-term well-being.

Only orphans adopted by foster homes before the age of two were able to develop emotional control abilities equivalent to those of never institutionalized children in research at a Romanian orphanage 6. Those who remained at the orphanage were deprived of social interaction and maternal care, and as a result, grew up with poor emotional regulation later in life.

The sensitive period of emotional self-regulation is therefore believed to be from birth to age 2.


Various visual functions of the visual system have different crucial times. They generally occur between puberty and are eye-opening.

For example, research reveals that visual acuity typically increases from birth to approximately the age of 5, with the largest growth occurring between the ages of 3 and 5. Stereopsis, or the perception of depth, on the other hand, has a crucial phase that ends at the age of two.

Damage susceptibility in visual development has its own crucial time. For example, amblyopia, a condition in which one of the eyes has decreased vision because the eye and brain are not operating correctly together, can occur between the ages of several months and 7 or 8 years.

Absolute Pitch

Absolute pitch is the capacity to recognize and reproduce the pitch of a musical note without the use of other sounds as reference points.

Children who began musical training between the ages of 4 and 6 are the most likely to achieve absolute pitch.

However, training after the age of nine seldom results in that degree of skill in adults.

Auditory Processing

The absence of auditory information from birth can impair the normal development of a functional auditory system in children born with congenital deafness, significantly limiting their capacity to learn to talk.

Scientists discovered that if cochlear implants are implanted in these childrens before the age of 3.5 to bypass the non-functional inner ears, they may most likely learn to talk effectively, especially if they are also exposed to language-rich settings.

Language Aquisition

The Crucial Period Hypothesis, as applied to language acquisition, says that there is a critical period during which individuals are more capable of acquiring new languages with native-like ability.

This stage begins in early childhood and ends just before puberty begins.

Even in a linguistically rich context, acquiring new language competency 3 becomes considerably more difficult after this window, and complete mastery is improbable.

Eric Lenneberg, a linguist and neurologist, popularised the original concept in his seminal book Biological Foundations of Language in 1967.

This idea holds that the process of acquiring a new language is restricted by a critical period. There is a clear gap in results between learning within the crucial time and learning outside of it. The moment of discontinuity corresponds to the end of the crucial period.

However, we know that it is still possible for adults to acquire a new language after puberty, albeit it is more difficult and may take longer than for young children.

Thus, learning flawless phonology and grammar in a second language has a critical time, but learning (as general speakers) appears to have a sensitive phase rather than a critical period (although this alternative term is still debated and individual effect varies).

What Parents Need To Know About The Critical Period

The fact that there are so many distinct important stages in the brain development journey may seem daunting.

Parents who have “missed” some of the crucial stages are concerned that their children will fail. Those who have successfully “met” the key times feel relieved that their children are now prepared for life and that their tasks are completed.

The fact is that none of these statements is correct.

The idea of critical time is a contentious one in science since it implies a strict cutoff. If the talent is not acquired throughout that time period, the potential to develop this function will be lost for good.

However, some of those talents are experience-expectant rather than experience-dependent, which means that the stimuli necessary for growth are anticipated. The expected sensations, such as language, vision, and hearing, are almost certainly present in everyday life. It is unusual for parents to have to make an effort to impart such common experiences.

Experience-dependent abilities are those that rely on the existence of certain experiences. Parents must offer adequate early life experiences for their children in order for these talents to develop. Emotional control, a second language, and absolute pitch are a few examples.

However, many experience-dependent characteristics have sensitive rather than critical periods, which is excellent news. Even if the specific life events are not available at the ideal time, the talents can nevertheless develop. It might just be more difficult or take longer.

Among the experience-dependent talents, emotional regulation is by far the most important for a childrens development and future well-being. The most essential thing for parents to do is to offer a caring atmosphere for their children and to assist them in developing resilience.

The Critical Period

As parents, we must ensure that our children do not miss out on essential experiences, especially during key times. However, this does not imply that we should buy the latest “Mozart for Babies” DVD or enrol our toddlers in a slew of enrichment programmes. Our children require a loving atmosphere as well as exposure to everyday life events such as chatting, playing, and reading to them. Other underlying causes may also have an impact on the outcomes.

There is also no need to worry about missing out on the best opportunities because it is never too late to begin giving our children positive life experiences.


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