This week started normally with a quiz and a lecture and on Tuesday we visited the Cognitive Brain Research Unit in the University of Helsinki. The chapter for the quiz was about the wiring of the brain. The topics were a bit more difficult than before in our opinion but the lecture after the quiz clarified some things. We for example studied the production process of neurons, which includes cell proliferation, migration and differentiation. On the cell profileration, precursor cells are neural stem cells. Immature neurons are called neuroblasts and they were pictured slithering upwards to the cortical plate through the subplate in the migration phase. At first this mechanism seemed quite strange. The whole neurogenesis process includes neural precursor cells production in the lateral ventricle area, migrating neuroblasts and finally newly generated neurons in the cortical plate. The neuroblasts always go on and form a new cortical plate, which then becomes a new layer. The differation order is neurons first, actrocytes second and oligodendrocytes last.
After the migration the neurons begin forming an axon and the axon travels from the gray matter to the deeper structures in the white matter. Guidance proteins either attract of repel the axon, which guides to axon into a correct direction. There was a good demonstrative video from youtube of this topic, which helped understanding this. There was also interesting information of the connection between neurotrophins and apoptosis. The survival of neuron depends on neurotrophins provided by target neurons and without the neurotrophins, apoptosis (systematic disassembly of a neuron) begins. Neurotrophins switch off the apoptosis.
The excursion was very interesting but seemed a bit rushed at times. First we visited the no interference room where the test subjects watch silent movies while their brain reactions are tested. After that we had a little presentation of the areas experimented in this unit. We found out that sounds development is affected by native language learnt as a child, particularly the difference between Finnish and Estonian language development. The difference was apparently due to the differing ö and õ sounds, which was interesting to know. We also saw how neural sound discrimination can be improved in dyslexic children using audio training game and a comparison of how MMN differs for different types of musicians. There also seemed to be a correlation between positive brain development and learning music, which was interesting. Furthermore, only listening to music is believed to improve verbal memory, mood and attention.
- Pekko & Maria