S4: Normal Psychomotor Development

Question 1

What is the definition of psychomotor development?

Answer 1

It is the progressive (gradual) attainment of skills that involve both mental and muscular activity. Examples include the ability of an infant to turn over, sit up, crawl when it wants and the toddler to walk, talk, control bladder and bowel functions and begin solving cognitive problems.

Question 2

What is the 2 steps in formation of the CNS I?

Answer 2

Initially there is:

1. Formation of the neural tube.
2. The development of the prosencephalon (forebrain).

Question 3

Describe formation of the neural tube

Answer 3

• Primary neurulation, starting off with thickening of the neural ectoderm which forms the neural plate.
  The edges of the neural plate start to fold upwards and over these are the neural folds, forming a ditch in the middle called the neural groove.
• The neural folds go further up and eventually meet, causing the neural tube to pinch of the ectoderm. There are three layers of the neural tube, the outer marginal layer that will form the white matter, the middle layer that will form grey matter and the inner layer will form the lining of the ventricles in the brain.
• The neural crest cells are very important, these are at the ends of the folds and will form many structures e.g. ganglia.

Question 4

Describe the development of the prosencephalon

Answer 4

• By the fourth week the neural tube has developed into the prosencephalon, the mesencephalon (will form midbrain) and the rhombencephalon.
• At the 5th week the prosencephalon divides into telencephalon and diencephalon. The rhombencephalon divides into the metencephalon and myelencephalon.
  Inferior to the myelencephalon is the spinal cord.
• If these processes go wrong, it will likely result in neural tube defects. We know that mothers not taking folate supplementation periconceptially and or in early pregnancy are at increased risk of having a baby with neural tube defect.

Question 5

What is anencephaly (example of NTD)?

Answer 5

• An example of a neural tube defect is anencephaly. This is caused by a failure of the anterior/cranial neural tube (neuropore) to close.
  The prosencephalon remains in contact with the amniotic fluid and degenerates, there is also an open skull as cranial bones don’t form.
• Lots of these babies will be stillborn, those that survive will likely only survive a few days maximum. Most pregnancies will be terminated if this defect is found.

Question 6

What is spina bifida (example NTD)?

Answer 6

Neural tube defect caused by failure of the caudal to close. This is spina bifida, a defect where there is incomplete closing of the backbone and membranes around the spinal cord. There are three types, myelomeningocoele is the worst type of spina bifida.
The spinal cord enclosed in membrane comes out of the back. The most common location for spina bifida is the lower back.

Question 7

What is holoprosencephaly (example NTD)?

Answer 7

The next neural tube defect is holoprosencephaly. This is when the proscencephalon doesn’t split and remains as one sphere. So the brain doesn’t have two hemispheres.
Defects occur in the development of the face and brain function, most severe types are stillborn.
Milder phenotypes will have severe facial defects, some may only have one eye and missing the nose.

Question 8

What is the 4 steps in formation of the CNS II?

Answer 8

The basic brain structure has been discussed however the neurones of the brain also need to be developed and connected up. There are quite a few steps involved in this process:
1. First there needs to be neuronal proliferation, this is the production of the neuronal mass of the brain.
2. Then is neuronal migration, where the neuronal cells migrate to where they need to be.
3. Neuronal organisation involves circuit formation
4. Myelination occurs.
All these events span from the second month of gestation right up into adult life.

Question 9

How does brain growth change after birth?

Answer 9

There is very rapid rate of brain growth after birth and for the first years of life. This is due to formation of dendritic connections and continuing myelination.
From adulthood, brain mass starts to decline. Once in old age, brain mass is notably less and there is a decline in cognitive function.

Question 10

Describe neurodevelopment throughout life and what influences development

Answer 10

• At birth: The cerebral cortex is primitive and our neurones are relatively poorly connected
• As we get older in early life, there is physical growth of the nervous system through myelination of nerves and increased connections between neurones.
  As myelination continues to progress, we see that the nervous control of functions begin to improve and this continues into childhood.
• Both biological influences and environmental influences will affect a child’s developmental progress. In other words how well they develop. It could be said that the biological influences determine the potential of the child and the environmental influences will determine the extent to which this is reached e.g. deprivation.
• For optimal development the environment should meet the child’s psychological/emotional and physical needs. A baby just really requires physical needs but as the child gets older, psychological/emotional needs start to become more important. This is as the physical needs of the child become less as they can do more themselves.
• The main role of developmental paediatrics is to help children achieve their full developmental potential. To do that clinicians need to detect and manage any developmental delay as soon as possible.

Question 11

List properties of development of children

Answer 11

• Innate.
• Incremental (steady progress).
• Progressive.
• Responsive to stimuli.
• Interdependent.

Question 12

What are developmental milestones?

Answer 12

• When a parent comes into clinic they want to know if their child is developing normally and indeed normal development does follow a recognised sequence of attainment of skills at different ages.
• These are the developmental milestones: the age at which major skills that are crucial to a child’s progress in each of the four spheres of development are achieved.
• Paediatricians use developmental milestones to see if a child is developing normally.

Question 13

What are the 4 spheres of developmental milestones?

Answer 13

Gross motor e.g. sitting, walking and running.
Fine motor e.g. hand skills, visual development.
Communication e.g. speech and hearing.
Social and Emotional e.g. feeding, dressing, social relationships.

Question 14

Describe gross motor developmental milestones

Answer 14

Newborn they can reflexively head turn and move head side to side.
At 6 months the average child can sit alone for 30 secs or more.
Crawling on all fours (8-9 months)
12 months some children are walking independently.
By 18 months children can generally run around.
2,3,4yrs walking up stairs.
Complex motor play (4-5 years).

Question 15

Main stages of developmental sitting

Answer 15

Around 3 months, can’t sit on own but some control of neck.
6 months, can sit on his own in a tripod position.
8 months, sitting unaided.

Question 16

Describe normal variations in patterns of movements

Answer 16

There are normal variations in patterns of movement, for example some move by bottom shuffling, some by commando crawling, some crawling on all fours.
Crawling standing and walking is the most common, children that follow this pattern they will learn unsupported sitting at 7 months, standing at 9.5 and walking alone by 13.5 (on average).
- 6% of the population miss out standing and go straight from crawling to walking, they will learn to sit, stand and walk earlier.
- 9% will bottom shuffle
1% creep/roll (commando shuffle).
These are normal variations, but in some cases alarm bells may ring if there is reason to believe there is neurodevelopmental problems e.g. cerebral palsy.

Question 17

Describe fine motor and vision developmental milestones

Answer 17

Fine motor skills require visual skills e.g. knowing how to draw. Therefore if there are problems with fine motor skills we need to determine if a visual problem is the cause.
At 3-4 months baby starts to look at hands.
6 months starts to transfer objects from hand to hand.
9 months start using a pincer grip.
14 months able to use a pencil and build block towers.
At 3 should be able to copy a circle.
4.5 should be able to draw a square.
6yrs a triangle.
Thus we can see that child motor skills we test using how many blocks they stack and if they can take it down again.

Question 18

What are the primitive motor reflexes we are born with?

Answer 18

There are number of primitive reflexes that newborns are born with, these should all disappear by 6 months in order for the infants motor skills to progress. If they haven’t disappeared by 6 months then this is a sign there is a problem. Primitive reflexes include:

• Moro reflex -> Arms will go out and in on sensation of being dropped.
• Rooting -> Stroke babies face gently and baby will turn towards stimulus and try suck.
• Grasp -> Baby will hold you if you put something e.g. finger in their hand.
• Placing.
• Stepping -> Hold a baby up vertically with feet on a hard surface, baby will show stepping movements.

Question 19

Describe speech and hearing developmental milestones

Answer 19

Newborns will be startled by noises.
By 6 weeks baby should able to recognise mothers voice.By 6 months the baby should be able to babble.
By 8 months using “mama” and “dada” non-specifically (i.e. use for everyone).
By 12 months uses “mama” and “dada” specifically.
16 months can point to body parts.
2yr old should know about
50 words.
2.5yr old knows individuals first and last names.
3yrs of age a 250 word vocabulary.

Question 20

Describe social and emotional skills developmental milestones

Answer 20

Newborns can regard peoples faces.
6wks can smile.
6 months can give discriminated smile to things they enjoy.
7 months display stranger danger anxiety.
10 months can wave goodbye and play peek-a-boo.
18 months uses spoon.
2yr olds play on their own (parallel play).
3yrs play interactively with other children.

Question 21

Describe how the developmental milestone sphere scales are interdependent

Answer 21

The different spheres have been discussed and they are interdependent, meaning that in order to progress they in part rely on one another functioning properly. Fine motor is interdependent with gross motor. Gross motor is interdependent with vision because you have to be able to see what you’re doing. Social and vision, as involves interaction. Hearing on gross motor as need to be able to audibly discriminate the command.

Question 22

What is developmental delay?

Answer 22

Developmental delay is defined as failure to acquire a particular developmental skill at an age when 95% of peers have done so.

Question 23

What are the two patterns developmental delay can be divided into?

Answer 23

1. Global delay is delay in 2 or more areas of development and it is the result of a widespread problem esp. if delay in all four areas. It is most likely a widespread problem of brain structure due to genetic causes, asphyxia at birth, infection or trauma. Another problem could be a lack of sensory input, this is often seen in severe neglect of a child.
2. Specific delay is being delayed in one of the areas of development and is the result of a more targeted discrete abnormality. It could be a specific/discrete problem of the brain e.g. speech delay or some blindness. There could be a defect with muscles e.g. myopathies or neuropathies. There could be a defect of specific sensory organ e.g. blindness or deafness.

Question 24

List examples of cause for concern developmental delays

Answer 24

If baby not smiling by 8 weeks.
If not achieving eye contact by 3 months.
If not reaching for objects by 5 months when on play mat.
If not walking unaided by 18 months.
Not saying words with meaning by 18 months.
No 2-3 word sentences by 18 months.

Question 25

Describe the diagnostic approach to detecting and diagnosing developmental delay

Answer 25

• Screening: A doctor or specialist midwife will screen the newborn for various developmental signs. At 6 weeks screened again at GP (e.g. is baby smiling?), health visitors then screen at 6-9 months, 18 months and at 3yrs of age.
• Evaluation of Development. If in the screening something appears not to be right then the child will be brought into clinic, be assessed in detail and given a score for development (e.g. Griffith’s developmental scores).
• Looking for Causes: If the score indicates delay, then the cause needs to be identified. There can be many possible causes e.g. chromosomal in which case make a referral to genetics, possibly a brain defect in which case get an MRI, is there a hearing problem if so refer to audiology, refer to ophthalmology if visual abnormality suspected, is thyroid function normal if not refer to paediatric endocrinologist?
• Correct what can be corrected: Prevent the cause impacting on development e.g. if deaf get hearing aids asap, if blind try improve sight, if hypothyroid give thyroxine/solve.
• Promote development: The skills are interdependent so by avoiding delay in one sphere/scale you will help prevent it impacting on other spheres. This is why it should be corrected quickly.

Question 26

List risk factors for global developmental delay

Answer 26

Inequalities in Early Childhood:

• Linear growth restriction.
• Inadequate cognitive stimulation.
• Iron deficient or anaemic.
• Exposed to lead.
• Violence at home.
• Poor maternal nutrition during pregnancy.