Lecture 13 Flashcards
Discuss brain development
Brain volume quadruples between birth and adulthood because of a growth of synapses, dendrite and fibre bundles. The brain also increases in size due to axon myelination. Sensory areas myelinate before motor areas. This all happens because as you learn, new connections are formed which makes pathways more complex.
Discuss what stimulates foetal receptors
Exteroceptive somasthetic stimulation: the foetus can feel the mother’s movements like rocking in a chair. Also they are sensitive to pain and temperature.
Olfactory and gustatory stimulation: they are sensitive to chemosensory molecules in the amniotic fluid.
Vestibular stimulation: they are sensitive to changes in orientation and changes in velocity. Also, they are sensitive to vibrations.
Visual stimulation: they can feel the difference between light and dark due to energy waves.
Discuss the timeline about the beliefs about prenatal stimulation
In the 1700s, they believed sensory isolation was existed. In the 1800s, they believed relative isolation occurred. Then in the 1900s, all stimulation, other than vision and olfaction, exists. It is believed that one should enhance their sensory experience but too much stimulation is bad.
Discuss examples of prenatal learning affecting postnatal behaviour
The flavours in the amniotic pool create preferences in taste of the neonate. They’re attracted to the complex amniotic smell. Neonates are also more responsive to the mother’s voice as they learnt what it sounded like in the womb. They are also more responsive to passages read to them in the womb. Neonates can discriminate between happy and sad emotions in the mother. Also, their crying patterns have been found to follow pitch structure of their culture (french rise in pitch at the end of sentences). Babies in the womb also show happy expressions as well as expressions of pain. Furthermore, twins in the womb move slower towards each other vs the uterine wall as they don’t want to harm the other twin.
What is Apgar scoring?
What about the NBAS?
It’s a technique that’s used to check how healthy and developed neonates are. However, it doesn’t check how normal their behaviour is, it just looks at aspects like heart rate, muscle tone and skin colour.
The NBAS however looks at behaviour more, it measures aspects like orientation/reactions to animate objects, cuddliness and the pull to sit method. This shows how developed the neonate is.
What preferences do almost all babies have?
They have preferences for people with attractive faces, after 3 months, there are preferences towards people of the same race. They have preferences towards the human vocal range, they prefer females voices and prefer their mother’s voice. They show all basic emotional expressions from birth.
Disuss foetal sensory development
It’s a fixed sequence. The foetus develops touch after about 50 days, vestibular sense after 100 days, auditory after 150 and visual after 180. However, the receptors for these senses are protected (eyelids fuse, finger tips covered in skin pads and sound transmission is blocked) during the formation of thalamocortical projections.
List some neonatal reflexes
The palmar grasp: neonates can hold their own weight from a washing line.
Moro reflex: when they lose their support, they reach up and grab for something, presumably the mother.
Research babinski reflexes.
Primary walking reflex: if supported neonates can walk, however, they lose this skill over time due to the developing cortex inhibiting it. However, it could also be inhibited due to a change in weight changing equilibriums. Some research has found that is doesn’t disappear if it’s regularly practised and can induce secondary walking sooner.
Discuss conditioning in neonates
Blass et al classically conditioned 2 hour old babies to associate forehead stroking with sucrose, they would begin sucking when stroked.
Siqueland et al instrumentally conditioned 4 day babies to turn their head to the correct side when reinforced with dextrose water solution.
What is neonatal reaching?
Neonatal reaching is when they grab and reach for things randomly despite if there’s extra weights on the arm. It’s a technique to explore, test and develop visual control.
Discuss neonatal imitation
There is a lot of evidence for and against the idea of imitation. Studies have shown an imitation of oral gestures, finger movements, facial expressions and vocal sounds. 30% of normal neonates don’t imitate and those who do follow different patterns (some imitate immediately, some have intense concentration etc.). Imitation can increase heart rate and provocation can decrease heart rate. It’s unknown how they are able to do this before ToM kicks in, it could be down to reflexes or it could be intentional or it could just be a form of oral exploration. It could even be because of mirror neurons (neurological bridge between people). It’s unknown what benefit imitation has, there are hundreds of ideas but it’s unknown. Neonates can engage with people from birth.
