Question

1/ Sleep is a behavioral state and play a key role in cognition. So how is it that sleep disorders (which are associated with NT release by neurons in the brain stem ) alter the cerebral cortex to ultimately affect cognitive function?

2/ Explain one way in which neuroplasticity allows learning and memory to occur.

3/ What do you think Wernicke’s area of an infant develops prior to Broca’s?

4/ Create a short paragraph using the following terms: fovea, cones, rods, peripheral retina, acuity, center of the visual field (10pt)

Answer 1

1. Neurons in the cerebral cortex become activated during sleep episodes with high slow-wave activity (SWA). The characterised properties of these neurons are the ability to produce nitric oxide and their long-range projections within the cortex. The characteristics of sleep-active cells produce SWA in the cortex. SWA is considered to be an indicator of sleep need that increases with time awake and decreases as sleep need is satiated during sleep. The gene Fos has been widely used as a marker of neuronal activity. the expression of Fos is induced during recovery sleep (RS) after a period of sleep deprivation (SD).

2.
Neuroplasticity is an amazing capacity of the human brain to change and grow throughout a person’s lifetime. It happens when new connections between brain cells form and strengthen, causing changes in the brain’s anatomy and chemistry in response to experience, environment, relationships, emotions, and many other influences. The more a person use, the more it improves.

The more two neurons work together, the stronger the synaptic connection between the two strengthens. A single neuron may have thousands of synaptic connections with other neurons, with the average adult brain having some 500 trillion synaptic connections, and capacity for 500 trillion more. People can strengthen synaptic connections to help them perform better in their profession and other fields by providing mental cross-training that helps people explore new thought patterns and develop neuroplasticity, innovation, and problem-solving.

3.The part involved in lexical or semantic analysis, is associated with Wernicke's area and develops prior to Broca's area. Babies aged 22 to 140 days are capable of detecting consonant-vowel changes much better in the right ear (left hemisphere) than the left one (right hemisphere), a finding which indicates that the left hemisphere is likely involved in processing language-related signals right from birth. These brain areas are similar to the language reception areas in adult brains i.e, Wernicke's area in the left hemisphere.

4. Rod cells are nerve cells located largely outside the macula (the center) of the retina. The rods are responsible for peripheral vision, night vision and low-light vision but are not sensitive to color, as opposed to central vision. Cone cells are concentrated in the fovea centralis. Rods are absent there but dense elsewhere. Measured density curves for the rods and cones on the retina show an enormous density of cones in the fovea centralis, which is attributed both color vision and the highest visual acuity.

Vision within the fovea is generally called central vision, while vision outside of the fovea, or outside the foveola, is called peripheral, or indirect vision.