STROKE - Anatomy of the brain, part 2

To be able to understand what happens to our bodies in the event of a stroke, we must first begin to understand the brain.

If you missed my last post, STROKE - Anatomy of the Brain, part 1, you can find it here.

In my last post I talked about how the brain is divided into three areas, the brain stem,  cerebellum and cerebrum.  How the cerebrum is made of two halves or hemispheres and each hemisphere is divided into portions called lobes.

Today, I'm going to go into a little more detail on the brain's hemispheres and lobes.  

Right hemisphere

• The right side of the brain controls artistic functions such as music, awareness of art and insight. It also controls the ability to understand spatial relations, recognize faces and focus your attention on something. People with a stroke on the right side may have trouble with these functions.

Left hemisphere

• The left side of the brain is responsible for scientific function, such as the ability to work with numbers (mathematical skills) and reasoning. It also is largely responsible for the ability to understand spoken language and the written word.

The lobes

The entire cerebrum is made up of two layers. The outermost layer is called entire cerebral cortex (gray matter).   The cortex is deeply wrinkled and three of the deepest folds are used to artificially divide the hemispheres into four distinct areas or lobes.

• Frontal lobe: In each hemisphere, the frontal lobe is responsible for movement (motor functions). A stroke in the right side of the frontal lobe will affect your ability to move the left side of your body, and vice versa.
• Parietal lobe: Behind the frontal lobe lies the parietal lobe. It is concerned mainly with sensory activities, such as receiving and interpreting information from all parts of the body. A stroke to the parietal lobes in the right hemisphere can cause agnosia, which means you can feel, see and hear, but may not be able to understand what you are perceiving. In other cases, a condition called neglect may develop. People with neglect have many sensory problems on the stroke-involved side of the body. As a result, they may ignore everything on that side.
• Temporal lobe: The temporal lobe controls hearing and memory and is also involved with auditory perception. Strokes in the temporal lobe of the dominant hemisphere (usually the left hemisphere) can cause a speech disorder known as Wernickes aphasia. Memories are stored in the inner part of the temporal lobe. Unless both the left and right lobes are damaged, memory loss after stroke is usually only temporary.
• Occipital lobe: The occipital lobe lies at the back of the head and is responsible for vision. A stroke in the left occipital lobe may result in losing the right side of your vision. Damage to the right occipital lobe can cause vision loss on your left side. In both cases, the eyes are functioning normally and the problem lies with the brain's ability to process information from the eyes.

Over several Wednesdays I will offer information on the following - 

• Anatomy of the brain √
• Ischemic stroke - next Wednesday
• Transient Ischemic Attack (TIA or mini-stroke)
• Hemorragic stroke
• Stroke in children (Paediatric stroke)
• Effects of a stroke

 All information contained in this post was obtained, with permission, from the Heart and Stroke Foundation  website. Please visit their site for more information.

Monica
Disclaimer

The material provided on this site is designed for information and educational purposes only. The materials are not intended to be a self diagnostic and/or self treatment tool. I encourage you to use this information as a tool for discussing your condition with your health practitioner.