Cerebral hemisphere

Poles of cerebral hemispheres (en) - inferiror view

Human embryo 8 weeks 4

Sheep Brain Dissection 2 - black background with labels

Gray726-Brodman

Cerebral hemispheres are the two halves of the brain that are separated by the longitudinal fissure. They are known as the right and left hemispheres, each controlling different functions and aspects of human cognition and behavior. The brain's hemispheres are connected by a bundle of nerve fibers called the corpus callosum, which facilitates communication between the two sides.

Structure

The cerebral hemispheres are the most visible parts of the human brain. Each hemisphere is covered by a layer of neural tissue known as the cerebral cortex, which is involved in many high-level brain functions such as sensation, perception, memory, thought, and language. The cortex of each hemisphere is divided into four main lobes: the frontal lobe, parietal lobe, temporal lobe, and occipital lobe. Each lobe is associated with different functions and abilities.

Function

The two hemispheres of the brain are known to specialize in different functions, a phenomenon known as lateralization of brain function. The left hemisphere is typically associated with logical reasoning, analytical skills, and language processing, including speaking, reading, and writing. The right hemisphere, on the other hand, is more involved with spatial abilities, face recognition, visual imagery, and music.

This lateralization is not absolute, and both hemispheres contribute to most cognitive tasks. However, the dominance of one hemisphere for certain functions can be observed in most individuals. For example, in right-handed people, the left hemisphere is usually dominant for language and fine motor skills, while the left-handed individuals might have a more distributed or reversed dominance.

Clinical Significance

Damage to one of the cerebral hemispheres can lead to a variety of neurological deficits, depending on the location and extent of the damage. For instance, damage to the left hemisphere can result in difficulties with language (aphasia), while damage to the right hemisphere can affect spatial processing and visual perception. Conditions such as stroke, traumatic brain injury, and brain tumors can lead to hemisphere-specific deficits.

Research and Studies

Research into the functions and interactions of the cerebral hemispheres continues to be a significant area of study in neuroscience and psychology. Studies using techniques such as functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) have provided insights into the hemispheric specialization and the nature of interhemispheric communication.

See Also

• Brain
• Neuroscience
• Lateralization of brain function
• Corpus callosum