From a neuroscientific perspective learning means first of all nothing but the modification of synaptic transmission strengths. ie, that fall under the title "Learning at the cellular level" in principle, the neural mechanisms that are subsumed under the concept of neuroplasticity. The interesting thing about this situation is that learning is not only the "conductivity" between neurons improves (or worse), but changed through this process in humans. Changes the brain, so also changes the "I" which is created by it. Man is, once he has learned something different. After Spitzer learning in biological systems is not possible otherwise. ( see Spitzer 2002, p. 234)
Below I will in two separate points of both the neuro-plasticity and learning explain at the cellular level, with one implies the other. In particular, the second point I will use it to deepen the processes present.
neuroplasticity
(neuro-) is plasticity, including with respect to the subject of this work, perhaps the most important organizational principles of the brain. Neuroplasticity is defined by the Encyclopedia of neuroscience as ...
... " the variability of neural connections in the nervous system. The concept of neural plasticity is thus the recognition that the newly- neural connections are not fixed and invariable, but because of certain functional activity (eg learning) or they have lost of nerve cells or axons are subject to change "
( Joseph P. Hammer Head 2000, in: Encyclopedia of Neuroscience Vol 2 2000 p.85).
Joseph P. Hammer head still distinguishes between functional and structural plasticity. The functional plasticity in particular the change in the efficiency of synaptic transmissibility is meant, without leading to a change in the anatomical structure content. For example, perform an action potential in the präsynaptsichen termination of a neuron to an increased transmitter release, resulting in increased activation of postsynaptic a result. The structural plasticity differs from the functional is that it comes to anatomically tangible changes in the neural network. The anatomical changes, for example, relates to the molecular features of pre-and post-synapses, but also the structure the dendrites and may be associated with the formation of new synapses or new axons. All the processes of learning are based according to the neuroscientists on this plasticity and thus adaptability of the nervous system.
Menno Baumann points out however that a large disagreement about how large the scale really is, which can take these processes. On the one hand, he describes stood the skeptics, who both hold the potential of plasticity is very limited and the view of neural reorganization related to age or duration is limited. On the other side are those who the capabilities of the brain to reorganize as a very large estimate. Though agreement is the fact that the (neuro) plasticity is, and that in the early childhood subject to terms more favorable than in adults. ( see Baumann 2007 p. 91) This refutes the idea that " what not teach an old dog learn never more would "as an old dog learn faster, but adults in principle the Ability to neuroplasticity, have combined with the opportunity to build on previous learning experiences.
learning at the cellular level: Second Messengers, Langzeitpotenzie tion and representations
At the cellular level means learning that the communication, ie, the synaptic connections between nerve cells of specific circuits strengthened is. The basis of such changes is the formation of new receptors on the postsynaptic membrane, so that incoming neurotransmitters have more opportunities to transmit their signals to the downstream neuron. But it's the other way around too well, so a targeted reduction other receptors, for example, produce such, the inhibitory signals that also lead to a strengthening of synaptic connection between two nerve cells. ( see fire / Marko Witch 2006 : What does brain research on learning , in: Journal of Education Supplement 5 / 06 p. 28)
This nerve cells are stimulated to produce more targeted at specific receptors, there is needed neurotransmitters from the region of dendrites to the cell body reach, in order to influence the protein synthesis. Such neurotransmitters but must be coupled directly to the "success" of a synaptic connection, so only very efficient synapses between neurons are strengthened. For this purpose, there is an intracellular mechanism based on the so-called "Second - Messengers" is based. (ibid.)
The object of the second - Messengers is the information on the activation of a receptor molecule on the effect of . determine You can diffuse to the nucleus and thus inform the "nerve center" of the nerve cell through synaptic activity. This allows the synthesis of new receptors are introduced and thus strengthened the synaptic connection between neurons. The formation of second - Messengers is preceded by the so-called long-term potentiation. This refers to that because a high-frequency and long-lasting activation of nerve cells on the postsynaptic side of the processes that govern the formation of second - lead Messengers, to be strengthened. (vgl.ebd.)
The theory is based on long-term potentiation in the research of neuroscientist Donald Olding Hebb, who formulated a learning rule that states that whenever two connected neurons simultaneously are active, the connection between them becomes stronger. These processes leave a permanent mark caused by irritant effects from the outside. They selectively enhance the connections in the human brain and under depending on how people use it. These connections are reinforced for what did the man they "represent" what you have learned how the brain researchers say. Manfred Spitzer describes this as follows:
" The remaining traces of the fleeting impressions of out there in our ha ben a name: Man speaks of representations of the outside world. The se representations emerge and change, and is called GE precisely these processes as learning. Brains and their components, the neurons are specialized to form representations in relation to their environment and change it. Neurons represent certain aspects of the environment ... A neuron can can stand for something ... like a word with ... for something : "and added that :" We hold. It is said that the neuron represents something when it is activated, is this something processed by the brain. "
( Spitzer 2002, p. 12f)
Therefore, neurons, or are a composite of neurons in activities for the places we have seen and other things we have learned. It decides the brain, specifically the limbic system, which is important and what is not, as I shall hereafter seen. Let us therefore together: The brain is plastic, that it says has the ability to constantly adapt to the environment. Where: things you do often reinforce the connections between the neurons in the brain, which represent the same things done. The more often these compounds are used, the more stable they are and the quicker the relevant knowledge is available. Connections that are not used to be melted down or die.
It can be concluded from an educational point of view well-known: exercise makes perfect . In addition can conclude that the brain is always learning and in every situation. Moreover, the man determined to some extent even of his brain structure by using it in a certain way and he learns from birth to use it in a certain way. This constitutes a circular process by the possibilities that the man pre-defined by his brain, but he on the way in which uses opens up new possibilities and they only possible. On introducing this idea further, can be viewed as talents and interests of students in a new light. Talents could therefore not be congenital, but due to the fact that a person has engaged in more for various reasons with certain things. In principle, this also says that a child, provided it with a "healthy" brain in the world comes to learn almost everything, even when differences in brain structure at birth were, as one might train different skills specifically.
neurons learn in combination - How rules and form repraesentatio NEN - the example of language
reacts at the birth of infant still in all the 70 phonemes, there is. Was six months but, as can be proven, he makes a distinction between the sounds he hears every day in his native language and the sounds, which he does not hear. ( see Spitzer 2002, p. 65)
is The interesting thing is that the computer-simulated neural networks (with appropriate training) in learning the language just behave like children: you become acquainted with the exceptions, then the rules and they will first make an error when they over-regulate , eg apply the learned past tense of verbs and the objects. At the end of the process can apply both children and the neural network, the exceptions and the rule. So the mere fact that synaptic strengths are changed in network as a function of the learning experience it come about that the network dominates a rule. This is done by the often heard the regularities are extracted. It strengthen the neural connections that stand for words and grammatical rules, which are often heard. It should be noted that at no time a child, or the computer simulation of the network has a rule explicitly learned. According to Spitzer, it is not sen these rules, except as a description of the what has been learned. Brains are therefore to Spitzer as " Regelextrakti production machines to". The brain is functionally designed so that it will not learn general rules by this he didactical preparation for "consumption" enough. It extracts from the many examples that are perceived, the rule-like. ( ibid. p. 74 et seq)
general, the human brain can and insights from the outside world has two ways to represent: first, it can classify objects into relevant categories, on the other hand, as explained above, made general representations. The ability to classify objects into categories would thus be the "classical timpani", ie learning by heart in school, in accordance with the second option is more like a " meaningful " learning. For this type of learning found in the frontal cortex specialized neurons. In animal studies with primates, this hypothesis could be empirically with respect to visual perception. The research revealed that the perceived stimuli are first in the visual cortex of the occiput and then processed along a whole set of visual areas of the cerebral cortex. These range in turn forward to the lower temporal lobe. There are not now represented more corners and edges, colors, or movements, but The general object properties. ( ibid. p. 90)
concludes Spitzer for the (school) education that learning individual facts or events or memorizing For example, . superfluous mathematical formulas, if not inconvenient, since it will give the school the children skills they can apply to different situations or types of tasks. Facts that are only learned by heart "float", thus in a "vacuum" of the brain, and could not other types of tasks be applied. These, but some exceptions are made: For example, places and important events of personal life, ie content that is just not generally but specifically excluded from this type of learning. This fall, but not in the classroom.
So, ladies and gentlemen. For today it was again. In the next post, I dedicate myself to the theme "Learning and memory from a neuroscience perspective" and watch me at times, especially the factors affecting the success of learning from a neuroscience perspective interesting.
As always, I thank you very much for your attention and have a nice evening.
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