[Physics Class Notes] on Plasticity Pdf for Exam

Plasticity refers to the quality of an object to transform to any shape and size.

When an elastic material is stretched beyond its elastic limit, the material becomes permanently deformed. This permanent deformation is termed plasticity.

It means that when a material is subjected to a high magnitude of external force, its interatomic particles leave their old lattice points and become distant from each other.

Here, we will discuss elasticity, plasticity, types of plasticity, and plasticity psychology in detail.

Plasticity

Plasticity is the ability of solid materials to go with a flow or to change orientation permanently when they are subjected to stresses of intermediate magnitude between those producing temporary deformation and elastic behaviour, and those causing failure of the material to its original shape. 

Plasticisation is the influence of external forces that leads a material to undergo permanent deformation without rupture or damage. 

Elasticity enables a solid to return to its original orientation after the load or external force is removed. Plastic deformation occurs in many metal-formation procedures like rolling, pressing, forging, and in geological processes like rock folding and rock flow under the earth at very high pressures and at rising temperature.

So, the meaning of plasticity of a material is a material that can be moulded to any desired shape and size when subjected to high temperature and pressure.

Cortical Plasticity

We refer to cortical plasticity as neuroplasticity. It refers to the extraordinary ability of the brain to reorganize itself by forming new neural connections depending on their experiences, lifestyle, and environment. 

To collect information about the sensory experience and practised movements is a universal property of all cortical areas; and this capacity of the brain is known as cortical plasticity.

We observe that cortical plasticity is observed in variations that rely on experiences and in the functional attributes of cortical neurons and in the alteration of cortical circuits of the brain.

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Neuroplasticity Meaning

Neuroplasticity is the capacity of neural networks and neurons in the brain to change their connections and behaviour in response to the following:

1. Gaining new information

2. Sensory stimulation

3. Development

4. Damage, or dysfunction

Though some neural functions appear to be hard-wired in particular, localized regions of the brain, certain neural networks possess modularity and perform specific functions while retaining the capacity to divert from their usual functions and to reorganize themselves. Hence, we consider neuroplasticity as a complex, multifaceted, fundamental property of the brain. 

Neuroplasticity

Neuroplasticity was forwarded by well-known neuroscientists to study only for childhood, but after the research in the latter half of the 20th century, a study showed that many aspects of the brain can be changed or are plastic even through adulthood as well.

We call neuroplasticity both neural plasticity and brain plasticity. It is the ability of neural networks in the brain to bring alterations through growth and reorganization. 

These alterations range from individual neuron pathways making new connections, to systematic adjustments like cortical remapping. 

Neuroplasticity examples are circuit and network variations that result from learning a new ability, environmental influences, practice, and psychological stress.

Developing the brain (by elasticity) exhibits a higher degree of plasticity than the adult brain. However, Activity-dependent plasticity can have significant implications like healthy development, learning, memory, and recovery from brain damage.

Types of Neuroplasticity

There are two types of plasticity; these are as follows:

• Structural plasticity

• Functional plasticity

Structural plasticity is known as the ability of the brain to change its neuronal connections. 

New neurons are produced constantly and integrated into the central nervous system (CNS) throughout the life span based on this type of neuroplasticity. 

At present, researchers use multiple cross-sectional imaging methods (that is a magnetic resonance imaging (MRI), and computerized tomography (CT) to study the structural alterations of the human brain.

This type of neuroplasticity studies the effect of various internal or external stimuli on the anatomical reorganization of the brain. The changes of grey matter proportion and synaptic strength in the brain are considered as the source of study of structural neuroplasticity. 

Do you know that structural neuroplasticity is currently investigated more in the field of neuroscience in current academia?

Functional Neuroplasticity

Functional plasticity refers to the ability of the brain to alter and get used to the functional properties of neurons. The alterations may happen in response to activity-dependent plasticity in order to acquire memory or in response to malfunction or damage of neurons, i.e., reactive plasticity to overcome a pathological event. In the latter case, the functions from one part of the brain transmit to another part of the brain relying on the demand to produce recovery of behavioural or physiological processes. 

Plasticity Psychology

Talking about the psychological forms of activity-dependent plasticity, these involve synapses, i.e, synaptic plasticity. The strengthening or weakening of synapses often results in an increase or decrease in the firing rate of the neurons. This rising/decreasing is the long-term potentiation (LTP) and long-term depression (LTD), respectively, and they are considered as examples of synaptic plasticity that are directly linked with memory.