Neuroplasticity(1)

Refers to how the brain changes with learning and its application in rehabilitation.

Learning requires storage of memories, leading to physical changes in the brain.
The brain is constantly molded by experiences throughout life.

The brain is not fixed; it changes continuously with learning and experience.
Most learning involves rewiring, strengthening neuron connections.
Most neurons present at birth persist throughout life, but new neurons are generated in the hippocampus (a small area crucial for memory and learning).
Neuroplasticity plays a role in rehabilitation processes.

Plasticity is the ability of a structure that is weak to change due to external stimuli, maintaining enough strength not to mold all at once.
The human brain exhibits considerable plasticity (Hawkins SL et al, 2014).

Learning and memory are interlinked; physical changes in the brain result from learning experiences.
A common myth claims that the brain is fully developed in early childhood; however, learning and experience shape brain development continuously.
The brain undergoes adaptations based on genetics and experiences.

Neurons communicate via synapses, constituting a vast network that enables the brain’s computational power.
The brain contains approximately 86 billion neurons interconnected through about 150 trillion synapses.
Neuron connections constantly change; new connections (synaptogenesis) are formed, and existing ones are strengthened (long-term potentiation - LTP).

Described by Donald Hebb (1949): "neurons that fire together wire together."
When neurons fire simultaneously, the connection between them strengthens.
Frequent use of pathways reinforces and strengthens neural connections for learning.

Neurogenesis refers to new neuron growth in the hippocampus throughout life, crucial for memory and learning.
New studies show approximately 700 new neurons are added to each hippocampus daily.
While exciting, the specific roles of these new neurons in cognition and memory are still being researched.
Factors enhancing neurogenesis include exercise, diet, stress reduction, and learning, but their effectiveness on overall brain function is still uncertain.

Taxi Drivers & The Knowledge: They exhibit an enlarged posterior hippocampus associated with learning and memory.
Einstein's Brain: Studies found increased neural connections in Einstein’s corpus callosum, suggesting enhanced communication between brain hemispheres contributing to his intellectual abilities.

Neuroplasticity is the brain's ability to adapt structurally and functionally in response to stimuli; it involves changes in synaptic activity and connectivity (M. Puderbaugh et al, 2023).

The brain can reorganize and strengthen connections through repeated tasks.
Research increasingly focuses on how the brain can recover from injury via neuroplasticity.
Rehabilitation methods can remap functions from damaged areas to undamaged ones.

Neuroplasticity can change in response to injuries, with effects that may be beneficial, neutral, or negative.
Two primary mechanisms:
- Neuronal regeneration/collateral sprouting (including synaptic plasticity and neurogenesis).
- Functional reorganization (involving equipotentiality, vicariation, and diaschisis).

Incorporates various processes in response to damage, including unique mechanisms like functional reorganization.
As research advances, more targeted therapies may be developed for rehabilitation.

Involves using a mirror to visualize the intact limb, shown to enhance brain activation (Maier M et al, 2019).

A method used in stroke patients, engaging affected limbs in practice while constraining functional ones, showing increased brain activity (Johansen-Berg H et al, 2002).

Can also lead to negative effects (e.g., writer's cramp, phantom limb pain), associated with brain changes that produce harmful symptoms (Johnston MV et al, 2009).

Cajal, S. (1899). Comparative study of the sensory areas of the human cortex.
Maguire et al. (2000). Navigation-related structural change in the hippocampi of taxi drivers.
Maier et al. (2019). Principles of Neurorehabilitation After Stroke.
Johansen-Berg H et al. (2002). Correlation between motor improvements and fMRI activity after therapy.
Johnston MV (2009). Plasticity in the developing brain: implications for rehabilitation.
Hawkins SL (2014). The “Theatre” of Consciousness in Neuroscience History.
Mateos-Aparicio P et al. (2019). The impact of the study of brain plasticity.