Human Brain Structure Vindicates Nature's Engineering Ability

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More Major Components  Of The Human Brain Structure

Continuing our Brain structure tour, we get to meet more components of Nature's Masterpiece. She is ever ready to impress and satisfy the inquiring mind.

Cerebral Cortex

The Cerebral Cortex is the pink colored, outer-most layer, or crust, of the two Cerebral Hemispheres composing the Cerebrum.

Human Cerebral Cortex

It's Convoluted structure, consisting of Gray Matter, is thicker in Human Brain structures than other animals. And Neurons are more densely packed.

Although some creature's Brains, such as Whales and Elephants, are not far behind the Human Brain in Neuron density.

Accounting for approx forty percent of the Brain mass weight-wise, the Cerebral Cortex is subdivided into areas and labeled with their own designation of Cortex.

These subdivisions are designated according to their currently detected function, such as Motor Cortex, or Visual Cortex.

Not always appreciated as such by some members of our species, the Cerebral Cortex is considered to be the seat of intelligent behavior. This absorbing component of our Brain has connections, via our Nervous System, to all parts of the Body.


Our Mini Brain, the Cerebellum, resides comfortably just beneath the Occipital Lobe.

Human Brain Connections

With connections to the Pons Varolii, Medulla Oblongata, and our Cerebral Cortex, the Cerebellum is involved in all voluntary muscle movement, via sensory feedback.

Subconsciously coordinating muscle movement. Maintaining bodily equilibrium. That is our physical balance.

Learned physical skills and repetitive actions, memorized by, and recorded in the Cerebellum then become semi-automatic.

These learned physical skills and repetitive actions require little or no Conscious thought. Unless you want to improve on a particular skill.

The Cerebellum, saturated with Neurons, comes fully equipped with it's own Cerebellar Cortex, and is increasingly being associated with Cognition.

Basal Ganglia

The Basal Ganglia, in common with the Limbic, and other, subsystems of the Brain structure, are a formation of Nuclei in communication with several Brain regions.

In conjunction with the Cerebellum and Cerebral Cortex, principally the Motor Cortex, the Basal Ganglia complete the subsystem that controls physical movement.

Human Brain - Basal Ganglia

Basal Ganglia Circuits  Mikael Häggström MBBS, based on images by Andrew Gillies/User:Anaru and Patrick J. Lynch. Reproduced under  CC BY-SA 3.0

Unlike the Cerebellum, which takes most of it's cues from the external environment, the Basal Ganglia are concerned with internal cues and feedback.

Primarily involved with voluntary movement at the Unconscious level, the Basal Ganglia are also associated with physical habits. Both the forming of habits and the execution of habits, once formed.

Connections to various other parts of the Brain structure, including the  Prefrontal Cortex and Hippocampus, suggest they may be involved in faculties such as memory and learning, including higher Cognitive analytical activities.

The Basal Ganglia and Cerebellum are concerned with movement at an Unconscious level. The Cerebral Cortex is concerned with movement at a Conscious level.

In a continuing display of harmonious cooperation throughout the Brain structure, these three units work in synchronization to achieve their purpose.

The physical skills this accord permits are simply breathtaking.


Nuclei, plural for Nucleus, are assemblages of Nerve Cells, comprised of Gray Matter, or Gray and White Matter, varying in size, shape, and complexity, and having distinct functions. Typical examples being the Basal Ganglia, and Amygdala.

Distributed throughout the Brain structure and Spinal Cord, and elsewhere in the body, they constitute a vast communications system.

Gray Matter

Human Brain - White and Gray Matter

Gray Matter is composed of Neurons, (Nerve Cells) Glia, (support cells), Capillaries, (the body's smallest blood vessels) and Neuropil, the intricate network of connections formed from the Unmyelinated Axons, and Dendrites, of Neurons, along with Branches (Dendrites) of Glial Cells.

White Matter

White Matter is comprised of Myelinated Neuron Axons emanating from the Gray Matter, and Glial Cells. White matter derives it's description from the sheaths of Myelin encasing these Axons, which is, um, whitish. White matter contains more nerve fibers than gray matter and hence greater amounts of myelin.

Unmyelinated Axons are not insulated.

Myelinated Axons are insulated and conduct signals faster.


Myelin is a fatty substance, that protects, and insulates, the Axons. Appreciably increasing the speed of electrical signals within the Brain, and to and from the Brain, involving whatever destination, around the body.

Neurons and Glia

Human Brain - Synaptic Connection

Neurons Transmit and receive information via Electrical and Chemical signals, and form networks with each other from various parts of the brain, building and dismantling these networks depending on the individuals thought patterns.

Neurons consist of a Cell Body, one (usually) Axon, and varying amounts of Dendrites.

The more Dendrites a Neuron possesses, the more intricate the communication network it can establish with other Neurons.

There are two exceptions with Neural Cells and their Axons.

One exception is that Unipolar Neurons possess two Axons, and the other is Anaxonic Neurons, where Dendrite and Axon are elusively indistinguishable.

Human Brain Structure of Typical Neuron
Human Brain - Glial Cells

On going research indicates Glia may be implicated in more than mere support. This is exciting news. After being sidelined for nearly six decades, Science is again displaying interest in Glia.

Being ascribed new and important functions and properties, Glia provides many new research avenues with hugely important relevance to Brain structure and understanding Human intelligence.

Heavy Weight Brain Components Rock!

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We are all the same - except for one darn thing - we are all different

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