Cognitive development and difficulties

Cognitive development

Cognitive development is how humans acquire, organize and learn to use knowledge. In psychology, the focus of cognitive development has often been only on childhood. However, cognitive development continues through adolescence and adulthood. It involves acquiring language language development and knowledge, thinking, memory, decision-making, problem-solving and exploration. Much of the research on cognitive development in children focuses on thinking, developing knowledge and exploring and solving problems.

The most well-known model of child cognitive development was proposed by the Swiss developmental psychologist Jean Piaget, who divided children’s development into four stages. According to Piaget (1953), the developmental stages are universal, and the order in which they are acquired is fixed, with internalizing the actions from the previous stage being a prerequisite for moving on to the next stage.

According to Piaget’s (1953) model, in the first, sensory-motor, stage (0–2 years), a child acquires knowledge by observing and interacting with objects in their environment and moving actively. In their play, the child practises new skills by repeating various actions. For example, they may shake a rattle repeatedly to hear the sound it makes. When they notice that an action does not produce the desired outcome, the child gradually learns to adapt their behaviour, such as pressing a toy instead of shaking it to produce the sound.

In the preoperational stage (2–6, 7 years), the child shifts from sensory-motor thinking to symbolic thinking, when a child can use mental representations, such as symbolic thought and language. Children in this age group learn to imitate and pretend to play. This stage is divided into the preconceptual period and the intuitive thinking period. During the age of 2–4 years, children detach from the immediate physical environment and learn symbolic thinking, engage in imaginative play, reflect on past events and understand object permanence.

According to Piaget (1953), during the age of 4–7 years, children use intuitive knowledge, begin to understand conceptual categories and processes numbers. During the preschool years, 2–5 years of age, magical and wishful thinking emerges; for example, the sun went home because it was tired. This ability may also give rise to apprehensions with the fear of monsters, and having logical solutions may not be enough for reassurance. Similarly, conservation and volume concepts are lacking, and what appears bigger or larger is more. For example, one cookie split may be seen as two equal cookies. Read more about foundational mathematical concepts.

At the age of 6–12 years, the concrete operational stage, scientific reasoning and understanding of physical laws of conservation, including weight and volume, develop. Conservation means that children understand that certain properties of an object will remain the same, even when other superficial ones are altered. They know that when a tall, thin glass is emptied into a short, fat one, the amount of liquid remains the same (Piaget, 1953). Teachers should take into consideration the level of learners’ reasoning and understanding of conservation when they start to teach addition and subtraction as a concept of the conservation of numbers. For example: 3 + 4 = 4 + 3 = 5 + 2 = 6 + 1 = 7 + 0 = 7

The core ideas of Piaget’s (1953) stage theory regarding factors affecting development and children’s own activity in constructing their worldviews are still relevant, even though the theory alone cannot adequately describe the diverse qualitative changes in children’s thinking, task- and situation-based variations or individual developmental paths. For example, Piaget claimed that thinking in 4–7-year-olds is primarily egocentric (i.e. being unable to perceive that others can think differently than himself), whereas later studies have shown that even 5-year-olds can already understand other people’s thoughts and perspectives quite well. Piaget’s theory is important, as it has strongly influenced developmental psychology research and greatly increased understanding of child development, but it should not be relied upon entirely given current knowledge (Flightfoot et al., 2018).

Development of memory

The development of memory is an important aspect of cognitive development. Memory development is characterized by a drive for efficiency, even though the capacity of long-term memory is, in principle, limitless (we can learn an unlimited amount of new information). Not every observation is recorded in memory as a new individual memory with all its details; instead, new observations are combined with previous ones, categorized into broader groups, and irrelevant details are left out. The nature of a memory formed from a specific observation or experience is strongly influenced by the child’s age and developmental stage (i.e. how cognitively ready the child is to internalize and interpret their observations at that moment) (Saarinen et al., 2023).

Even foetuses can remember what they hear. For example, in a study by Partanen et al. (2013), pregnant mothers in the experimental group repeatedly played specific pieces of music, while the control group’s mothers were not. After birth, babies who had heard the music in utero showed greater brain responses to those pieces than babies in the control group (Partanen et al., 2013). Similarly, prenatal risk factors, such as maternal stress or exposure to foods not recommended during pregnancy, can predict poorer memory performance years after birth (Van den Bergh et al., 2020). Thus, learning and memory development already begin in the foetal stage, before birth.

In the early years, a child’s memory stores what could be considered ‘scripts’ about how certain everyday events typically unfold (i.e. what stages or outcomes are generally involved). These scripts develop for simple daily routines, such as eating, dressing or going shopping. Based on their experiences, children know that eating usually follows washing hands, walking to the kitchen, sitting at the table and placing the plate and cup on the table. Scripts are important because they help children understand recurring situations and anticipate them. As they grow, children come to understand more complex and multi-step scripts. For instance, by age four, children can usually follow three-step instructions or requests (e.g. Juma, please put on your pyjamas, brush your teeth and get into bed before I read a bedtime story to you) (Sax & Weston, 2007).

Memories of life events are referred to as episodic memory. Studying episodic memory in the early years is challenging due to limited language skills; it is often difficult to distinguish whether a child remembers events that they cannot express verbally. From about age three, children can recall past events, especially if they involved strong emotions, such as a stressful separation, or if they were involved in a unique event, such as a visit to the circus. How parents talk about events significantly influences memory recall. If parents reminisce about events with their child and ask questions such as ‘Where did you go yesterday?’, ‘Who did you meet?’ or ‘What did you do?’, these questions help the child structure events chronologically and improve their recall. However, children are also highly susceptible to errors – they may confuse memories, invent new details or become confused by leading questions. Children are also prone to mixing imagined events with real ones. This makes them particularly vulnerable to false memories, which is why children’s testimony in criminal justice proceedings requires particular care and professionalism (Wang, 2021).

Memory performance based on recognition is generally better than memory performance involving active recall, where a child must describe or recall a past event or experience in their own words. This difference is observed at all age stages but is particularly pronounced in preschool children. For example, in an experiment in which 4- and 10-year-olds were shown a series of 12 pictures, it was found that when they were later shown some of the previously seen pictures and new pictures, children of all ages were equally good at recognizing the pictures they had seen before. Differences appeared in active recall: 10-year-olds, without prompts, could describe the content of an average of eight pictures they had seen, while 4-year-olds could only describe two or three pictures (Yussen & Levy, 1975).

Working memory refers to the memory in which information from the senses and long-term memory is consciously and actively processed and integrated. The development of working memory is crucial for the smoothness of daily life, as it determines how a child can follow complex instructions using memory. For example, a 1.5-year-old child can generally process only one thing at a time and follow a single-step instruction, while a four-year-old can remember an adult’s three-step instruction.

Read more about working memory.

Cognitive milestones

Practitioners in ECEC centres are in a prime position to monitor the growth and development of children, particularly cognitive development. A lag in cognitive development may alert the carer, for example, to attention-deficit/hyperactivity disorder, learning disability, global developmental delay, developmental language disorder, developmental coordination disorder, mild intellectual disability, autism spectrum disorders, moderate-severe intellectual disability or vision and auditory disorders.

Therefore, observations in everyday situations are important, and lists of developmental milestones in cognitive development may help practitioners focus their observations on different age levels. Evidence-informed checklists can be used to support developmental surveillance and clinical judgment regarding cognitive development. These examples of cognitive milestones are based mainly on Zubler et al. (2022) regarding evidence-informed milestones for developmental surveillance tools.

Cognitive milestone	Age
Watches you as you move	2 months
Looks at toy for several seconds	2 months
If hungry opens mouth when she/he sees breast or bottle	4 months
Looks at his hands with interest	4 months
Puts things in her mouth to explore them	6 months
Reaches to grab a toy he wants	6 months
Closes lips to show she does not want more food	6 months

Looks for objects when dropped out of sight (such as his spoon

or toy)	9 months
Bangs 2 things together	9 months
Puts something in a container, such as a block in a cup	12 months

Looks for things he sees you hide, such as a toy under

a blanket

12 months

Tries to use things the right way, like a phone, cup

or book	15 months
Stacks at least 2 small objects, such as blocks	15 months
Copies you doing chores, such as sweeping with a broom	18 months
Plays with toys in a simple way, such as pushing a toy car	18 months

Hold something in one hand while using the other hand,

for example, holding a container and taking the lid off	24 months
Tries to use switches, knobs or buttons on a toy	24 months

Plays with more than one toy at the same time, such as

putting toy food on a toy plate

24 months

Uses things to pretend, such as feeding a block to a doll as

if it were food

30 months

Shows simple problem-solving skills, such as standing on

a small stool to reach something

30 months

Follows 2-step instructions, for example, ‘Put the toy

down and close the door’

30 months

Shows that he knows at least 1 colour; for example, pointing to a

red crayon, when you ask, ‘Which one is red?’	30 months
Draws a circle when you show him how	3 years
Avoids touching hot objects, such as stove, when you warn her	3 years
Names a few colours of items	4 years
Tells what comes next in a well-known story	4 years
Draws a person with 3 or more body parts	4 years
Counts to 10	5 years

Names some numbers between 1 and 5 when you point

to them

5 years

Uses words about time, such as yesterday, tomorrow,

morning or night

5 years

Plays attention for 5–10 min during activities, for

example, during story time or making arts and crafts

(screen time not counted)	5 years
Writes some letters in their name	5 years
Can tell you their name	6 years
Is learning to express themselves well through words	6 years

Can count to and understand the concept of 10,

for example, they can count 10 pieces of candy.	6 years
Copies shapes when drawing (circle, square and triangle)	6 years

Based on the table above, indicating typical milestones in cognitive development for various ages, here are some basic assessment activities that parents, educarers, student teachers and teachers can use to evaluate children’s progress.

Assessment of and intervention strategies to enhance cognitive development

Basic assessment of cognitive developmental milestones for various ages

Based on the table above, indicating typical milestones in cognitive development for various ages, here are some basic assessment activities that parents, educarers, student teachers and teachers can use to evaluate children's progress.

Now that the child has been assessed, what can be done to intervene to promote cognitive development? These are simple yet effective strategies that can be used for intervention, but more importantly, they should be the norm as far as possible. The aim is to create an environment that is conducive to effective cognitive development.

Intervention strategies for educators, student teachers and parents

Parenting and cognitive development

Good parenting is how parenting meets children’s needs according to the cultural standards that change from generation to generation. Cognitive development starts in the first year of life and then progresses gradually. Parenting gives a child the confidence to face crucial challenging problems. Sensitive parenting and caregiving are required for children’s maturity and cognitive development. Sensitive parenting is required for the proper cognitive development of a child. Proper emotional management is required for proper emotional regulation. Positive parenting helps children face non-social or social problems. Positive parenting is required for early cognitive development, emotional balance and maturation of thought, while negative, hostile parenting leads to depression and social and cultural problems. Parenting styles (authoritative, authoritarian, permissive and uninvolved parenting) have a psychological effect on a child’s behaviour (Lanjekar et al., 2022).

(Link to parenting if there is text somewhere else?)

Intellectual disability

ID refers to neurodevelopmental conditions that affect functioning in two areas (Patel et al., 2018):

Cognitive functioning, such as learning, problem solving and judgement

Adaptive functioning, which includes activities of daily life, such as communication skills and social participation

Additionally, intellectual and adaptive deficits begin early in the developmental period, typically before the age of 18 years for diagnosis. ID affects about 1% of the population, and of those, about 85% have mild ID. In high-income countries, 2–3% of children have IDs. Even with some fluctuation over the years regarding specific diagnostic thresholds, the primary criterion of a quantifiable score from a standardized test seems particularly clear and concise (intelligence quotient [IQ] below 70 in standardized intelligence tests). However, this apparent parsimony obscures the remarkable diversity of the people to whom the label of ID is attached and there is variability in their development across the life span. An IQ score of 70 has no particular scientific significance other than its convenient association with the statistical convention of two standard deviations below the mean, which in turn roughly reflects some general professional and societal consensus about the number of persons who require support and society’s ability and willingness to provide the necessary resources for them and their families (Burack et al., 2021)

There are many different causes of ID. Estimates of more than 1,000 different aetiologies highlight the genetic and phenotypic heterogeneity of persons with ID (Hodapp & Burack, 2006). It can be associated with a genetic syndrome, such as Down syndrome or Fragile X syndrome. It may develop following an illness such as meningitis, whooping cough or measles, may result from head trauma during childhood or may result from exposure to toxins, such as lead or mercury. Other factors that may contribute to ID include brain malformation, maternal disease and environmental influences (alcohol, drugs or other toxins). A variety of labour- and delivery-related events, infection during pregnancy and problems at birth, such as not getting enough oxygen, can also contribute to intellectual impairment.

With regard to cognitive functioning, even within the constraints of the breadth and sensitivity of standardized IQ tests and other indices of cognitive attainment, distinct patterns of relative strengths and weaknesses can be found for almost any of the different syndromes and conditions associated with ID (Burack et al., 2021). We may conclude that significantly below-average intellectual ability and level of adaptive behaviours are simply two symptoms shared by ‘a group of etiologically diverse conditions’.

Multiple studies have examined individual potential determinants of ID, but few have investigated holistically to identify the populations most at risk. A review of 58 studies (Leonard et al., 2022) indicated that there are vulnerable groups in which risk factors identified, such as low socio-economic status, minority ethnicity, teenage motherhood, maternal mental illness and alcohol abuse, may cluster, highlighting a target for preventive strategies. At-risk populations need to be identified and monitored so that interventions can be implemented when appropriate, at preconception, during pregnancy or after birth. This could reduce the likelihood of ID and provide optimal opportunities for vulnerable infants.

It is also important to understand IDs from the perspective of developmental psychology. Zigler’s (1999) conceptualization regarding the development of persons with familial ID is based on classic developmental theories (e.g. Piaget) in which (a) the order of attainment of functions or abilities is thought to be universal and (b) the many different aspects of functioning are organized in a relatively universal and systematic way that becomes increasingly complex over time. Every aspect of their developmental progression was expected to be similar to that of persons in the higher IQ ranges, albeit at a slower rate and with a lower ultimate level of functioning. Thus, even considering the large natural interindividual variability found in the general population, both the sequence and structure of development were thought to be relatively consistent across persons, regardless of their place along the IQ continuum. This means that children with IDs will reach developmental milestones later than expected (Ziegler, 1999).

According to Ziegler (1999), it is important to understand the ‘whole child’ and focus on social personality characteristics and ways of being that were often displayed by persons with ID in addition to the considerations of cognitive functioning. Apparently diminished performance could also be the result of styles of social interactions and responding that arose from the life experiences and the environments in which persons with ID live. Along with frequent experiences of failure, these life circumstances lead to the adoption of personality-motivational characteristics that would affect response strategies in general but particularly to experimental tasks that inherently occur in atypical and stress-inducing settings. The expectancy of failure can lead to a lack of trust in one’s own abilities or ideas and a subsequent look outward for direction from others on how to behave. These patterns are unique not to persons with ID but rather to the context, as they would be manifested by anyone who faced consistent failure in their lives (Burack et al., 2021; Zigler & Bennett-Gates, 1999). We may conclude that the development of typically and atypically developing children is similarly impacted by personality, motivational and other personal, familial and contextual factors.

Supporting children with IDs in ECEC

Introduction

Significant impairments in intellectual functioning and adaptive behaviour, which impact daily social and practical skills, are characteristics of ID. The deinstitutionalization of children suffering from ID is a global phenomenon. Most families raising such children experience a range of difficulties and require supportive systems to cope with physical, social and mental demands in a home environment (Modula, 2022). For such children, ECEC is essential to meeting their developmental needs. The goal of inclusive education, according to The United Nations Educational, Scientific and Cultural Organization (UNESCO) (2019), is to guarantee that all learners, regardless of their abilities, have equal access to high-quality instruction and meaningful engagement in classroom settings. To effectively support children with IDs, educators, families and professionals must collaborate in providing individualized instruction and creating supportive environments. This is the reason that early intervention can significantly enhance developmental outcomes and promote lifelong independence.

Early identification

Effective support for children with intellectual disabilities depends on early identification, as done in Kenya Institute of Special Education (KISE), for the purposes of detecting delays in language, cognition or social interaction. Many children with IDs or other developmental disabilities remain unidentified or underserved in their early years. Educators and caregivers should therefore monitor developmental milestones and utilize screening instruments (World Health Organization [WHO], 2020). Comprehensive evaluations, frequently conducted by interdisciplinary teams of educators, psychologists and speech therapists, help create individualized education plans (IEPs), which teachers tailor to the specific needs and strengths of each child (United Nations Children's Fund, UNICEF, 2020). As such, children can receive targeted therapies, such as speech, occupational or behavioural therapy, at a formative stage aided by early intervention programs, which also help close developmental gaps (American Psychological Association [APA], 2021). Effective learning and social inclusion are grounded in early action. Furthermore, regular observation enables teachers to adjust learning objectives or outcomes as learners progress in learning, ensuring ongoing and quantifiable progress.

Curriculum modification and instructional techniques

Early childhood settings must be deliberately inclusive, not just ‘take every child’ but adapt to children with IDs or developmental delays. Inclusive education demands a flexible curriculum that accommodates diverse learning abilities. To address each learner’s specific needs, teachers should differentiate their instruction by altering the curriculum, instructional strategies and evaluation techniques (UNESCO, 2019). Techniques such as visual aids, tactile materials, repetition and step-by-step instruction work exceptionally well for children with IDs. For children who process information more slowly, multisensory teaching – encompassing sight, sound and touch – enhances comprehension and retention (Kauffman & Hallahan, 2018).

Participation can also be improved by assistive technologies, such as interactive software, communication devices and visual aids. Teachers must emphasize social behaviour, communication and everyday living skills in addition to literacy and numeracy practiced in Kenyan early childhood schools and centres to balance the development of academic and functional skills (Smith, 2020). Young learners can become more self-assured and motivated by receiving regular feedback, employing positive reinforcement and acknowledging their little accomplishments. Children with IDs can learn alongside their peers in meaningful ways by embracing peer tutoring and small-group instruction, which also promotes social interaction and cooperative skills (Heward, 2020).

Supportive environment

A supportive learning environment is essential for the development of children with IDs. Structured routines, organized spaces and visual cues, such as schedules and symbols, help children understand expectations and reduce anxiety (Heward, 2020). Positive behaviour support focuses on reinforcing desirable behaviours, encouraging cooperation and building self-regulation rather than relying on punishment (Odom et al., 2017).

Creating emotional safety and promoting peer interaction are equally important. Teachers can foster inclusion through group play and cooperative learning, helping children with IDs form friendships and develop communication skills (Carter et al., 2020). Physical accessibility – such as adaptive furniture and sensory-friendly materials – ensures that all learners can participate comfortably. When classrooms are inclusive, predictable and emotionally secure, children with IDs are better able to focus, engage and grow academically and socially.

Family involvement

The prevalence of ID is high in Africa, particularly among low socio-economic communities. Despite this, there is limited literature on primary caregivers and parents of people with IDs regarding their experiences raising an individual with the condition, especially within the African context (Mkabile et al., 2021). Family engagement is a cornerstone of effective early childhood education. Parents and caregivers possess valuable insights into their child’s abilities, preferences and challenges. Collaborating with families in the development and implementation of IEPs ensures consistency between home and school learning environments (UNICEF, 2020). Teachers should provide regular updates on progress and offer guidance on supporting learning at home through simple play-based activities, such as storytelling, sorting and music – something encouraged a lot by the competency-based education (CBE) in Kenya currently.

Community awareness embedded in CBE’s community service learning and KISE outreach is also essential to combat stigma and misconceptions about IDs. According to the World Bank (2021), public education campaigns and inclusive community programs can promote positive attitudes and increase access to resources. When families, educators and community members work together, children with IDs receive consistent support that extends beyond the classroom. Furthermore, early childhood centres can organize parent meetings, peer support groups and awareness events that empower families to advocate for inclusive policies and improved services.

Professional collaboration

Teachers, therapists and caregivers must collaborate to support children with IDs. Working together guarantees that every child gets thorough and individualized support (Friend & Cook, 2020). Coordinated care, shared strategies and efficient monitoring are made possible by regular professional communication. Current findings suggest that there is a need for formal and alternative healthcare workers to work together towards an understanding and management of ID in Africa (Mkabile et al., 2021).

Another essential component of inclusive education is ongoing teacher training. Professional development sessions and workshops give teachers the tools they need to recognize learning difficulties, implement differentiated instruction and make effective use of assistive technology (European Agency for Special Needs and Inclusive Education, 2018). Incorporating families into this partnership enhances the comprehension of every child’s development. Early childhood programs can create cohesive, supportive environments that help children with IDs reach their full potential when families and professionals collaborate.

Promoting independence

Promoting independence and self-sufficiency is a key objective of ECEC for children with IDs. Life skills, such as dressing, feeding and basic problem-solving, are taught by educators and caregivers through repeated and structured practice. Self-confidence and autonomy are increased when self-expression and decision-making are encouraged (Smith, 2020). Including real-world activities, such as making snacks or setting up supplies, enables children to use newly acquired skills in everyday situations. In addition to fostering personal growth in children with IDs, this type of instruction prepares them for increased involvement in schools and the community. Programs for social and emotional learning can help learners enhance their communication, empathy and emotional regulation – all of which are crucial for social inclusion and long-term success (Heward, 2020).

Conclusion

It takes a comprehensive, inclusive and cooperative approach to support children with IDs in ECEC. Teachers can create opportunities for every child to thrive through early identification, individualized instruction, accessible environments, family engagement and professional collaboration. Encouraging potential, dignity and independence is just as important as granting access. The groundwork for just and caring communities that value all learners is laid when educators and caregivers see diversity as a strength. Therefore, encouraging inclusion in ECEC is a practical approach to accomplishing global educational goals as well as a moral requirement.

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