The human brain is anatomically composed of three general parts: the brainstem, cerebellum and cerebrum.
The brainstem is comprised of the midbrain, pons and medulla, connecting the cerebellum and the cerebrum to the spinal cord. The brainstem is particularly important because it manages automatic functions such as breathing, body temperature, heart rate, wake and sleep cycles, digestion, sneezing, coughing, vomiting and swallowing.¹
The cerebellum is located underneath the cerebrum, coordinating muscle movements and maintaining posture and balance.¹
The cerebrum is the largest portion of the brain, composed of left and right hemispheres which are divided into four lobes: frontal, parietal, temporal and occipital. The cerebrum is able to perform higher functions like interpreting touch, vision and hearing.¹
The cerebrum is covered in a folded material called the cortex. The cortex contains about 70% of the 100 billion nerve cells.¹ The cortex gets its colloquial name ‘gray matter’ from the grey-brown colour the nerve cell bodies make. Underneath the cortex, axons (connecting fibers between neurons) make up the white matter.¹
The seven major components of the brain in the hemisphere are separated into the midline, subcortical, and cerebral cortex.
The midline components include the brainstem, the cerebellum and the hypothalamus which control the hormonal system, drives like hunger and thirst, and body temperature.¹
The subcortical components include the thalamus, which delivers information from sensory organs and motor signals from subcortical structures to relay them separately to their respective cortices. There is also the basal ganglia which is a group of structures that exchange information with different parts of the cerebral cortex, playing a role in voluntary movement and learning and remembering how to perform a task.² The limbic system is an interlinked structure that is necessary for emotional memory.²
The cerebral cortex, as mentioned above, is the outer layer of the cerebral hemispheres of the brain. The cerebral hemispheres are divided into lobes. Each hemisphere has 4 lobes: frontal, temporal, parietal, and occipital. These lobes work together between the left and right hemispheres to serve a variety of specific functions. These functions are as follows:¹
Frontal Lobe
- Personality, behavior, emotions
- Judgement, planning, problem solving
- Speech: speaking and writing (Broca’s area)
- Body movement (motor strip)
- Intelligence, concentration, self awareness
Temporal Lobe
- Understanding language (Wernicke’s area)
- Memory
- Hearing
- Sequencing and Organization
Parietal Lobe
- Interprets language, words
- Sense of touch, pain, temperature (sensory strip)
- Interprets signals from vision, hearing, motor, sensory and memory
- Spatial and visual reception
Occipital Lobe
- Interprets vision (color, light, movement)
References:
1. Anatomy of the Brain. Retrieved from: http://www.mayfieldclinic.com/PE-AnatBrain.htm#.Uu0DY3ddWFk
2. Carlson, Neil R., Buskist, W., Heth, C.D, Schmaltz, R. Psychology - The Science of Behaviour.