What Is the Left Parietal Lobe?

The brain is the master center of the body. This complex structure, divided into three separate sections, the midbrain, forebrain and hindbrain, receives and processes sensory information and communicates this data to the appropriate body part to respond. Both the right and left parietal lobe are located in the forebrain in a section called the cerebral cortex.

The brain consists of areas of white matter and gray matter. White matter is like a courier, it transmits messages through different areas of gray matter. In turn, the gray matter, or the cerebral cortex, is responsible for the body’s reactions such as muscle movement and sensory perception. The cerebral cortex is further divided into two sections, the right and left hemispheres. Each hemisphere contains four lobes.

Each side of the cerebral cortex is divided into a parietal, frontal, occipital and temporal lobe; these mirror structures control opposite sides of the body. For example, the left parietal lobe, responsible for receiving and processing sensory information from the body, controls the right side of the body. Located towards the posterior portion of the top of the head, the right and left parietal lobe sits between the frontal lobe, the front area of the brain, and the occipital lobe or rear of the head.

When an injury is sustained to the parietal lobes of the brain problems can occur with words and numbers, in reading, writing and comprehending. Difficulties may also be present in distinguishing between the right and left side of the body and perception or the awareness of where the body is in space. This can lead to impairments with hand and eye coordination.

An injury or damage to the left parietal lobe of the brain can cause a medical condition called Gerstmann's Syndrome. This is a disorder that can cause problems with right and left discrimination, mathematical calculations and writing abilities. This syndrome may also cause aphasia, or impairment in speech, and agnosia, diminished capacity to distinguish sounds, shapes, smells and objects normally.

If an injury to the brain includes both the right and left parietal lobe problems with motor skills and visual skills may be present. This includes the inability to visually process the different components being looked at and having difficulties in controlling where the eyes fixate, otherwise known as visual gaze. Optic ataxia may also be present. This is a condition that causes patients to experience difficulties when attempting to see and reach for objects.