Neuroplasticity
Neuroplasticity is the property of human brain to continue information processing and ability to adaptively change in new environment, including post trauma survival.
One of the examples of brain plasticity is learning process. For instance, during learning data first enter the short memory which works mainly with one-side directed transfer of electrochemical signals. When significant activation happens (which also depends on the number of stimuli we experience: visual, audio etc. and our motivation), neurons not only pass signals, but also have a chance to get them back from a neighbouring neuron. Then, structural changes in neurons network happen and long term memory is formed. However, all the data which is not actively used will be gradually “weeded out” or undergo “synaptic pruning” – when old connections between neurons are deleted. Only actively used neurons will be supported and will form new synaptic connections. Yet, currently, it is not proved whether the data is permanently lost from long term memory, or just it is not possible to retrieve it, but the fact that we more easily recognize information than independently retrieve it supports the second point. The plasticity of the brain here is based on ability to store and rapidly provide information we need for everyday life and eliminate unneeded information. Yet, this process is never one-directed or hits unchangeable state. Even though brain neuroplasticity activity is higher before adulthood, it never ends in healthy individuals and it acts really rationally – probably that is the reason why we remember nothing about our early years.
Moreover, neuroplasticity in patients with disabling states in fact helps to recover, e.g. in patients with brain damage (stroke, trauma) or removed parts of brain, some brain functions are amazingly transferred to other parts of the brain (which usually do not perform those functions or even are not localized close to the injury site). (Watch the video about the girl with half of brain removed!).
Neuroplasticity is happening in number of brain locations simultaneously (see the picture) and is based on ability of neurons to build new connections and enhance old ones. Neuroplasticity in damaged brain can be classified into: “functional map expansion” (increase in volume of the brain region performing signals interchange for a specific body organ); “compensatory masquerade” (involving neighbouring to injury site areas into new function); “homologous region adoption” (distant function transfer); “cross-model reassignment” (substitute of damaged sensory input with another one).
The Source for the Background Image: http://www.learningrivers.com/WondersMetronome.html
Bilotkach Kateryna, UCI, BME 240, Spring-2009