Our brains are arguably the single most complex system known to man. Together with the spinal cord, the brain makes up the central nervous system, which controls every aspect of our lives; from breathing to solving math problems.
3 main sections comprise the brain: the forebrain, midbrain and the hindbrain. Each of these sections works together as well as independently to ensure we stay alive, know when we are hungry and help up stand up.
We will highlight these sections and explain their functions.
The forebrain is the largest part of the brain. It further divides into the cerebrum, thalamus and the hypothalamus. This section of our brain controls higher brain functions such as thought and action.
Also called the cerebral cortex, when you think about what a brain looks like, you usually picture the cerebrum. The cerebral cortex is again, further divided into 4 parts, or lobes:
- Frontal lobe – which gives us reasoning, problem-solving, emotions, speech and problem solving/planning.
- Occipital lobe – This gives us visual processing.
- Parietal lobe – This lobe controls our motor skills so we can move, equilibrium and our perception of external stimuli.
- Temporal lobe – The temporal lobe is associated with hearing, memories and speech.
Cortical folding (the wrinkles and folds in the gray matter of these lobes) allow us to have thoughts, be able to talk and understand language, use fine motor skills and use reason and logic. The more folds, the larger the available surface area to have and use these functions.
The cerebrum divides into 2 halves: the left and right hemispheres. The right hemisphere controls our creative and artistic abilities. Without this hemisphere, we wouldn’t have art, music, dance or poetry.
The left hemisphere controls reason and logic. This allows us to have reason, make decisions and solve problems. Without this hemisphere, we wouldn’t be able to recall facts and figures or understand mathematics and science.
The thalamus is the sensory never center of our brain. It receives sensory input from almost every part of our body. These signals travel through our nervous system to the thalamus which then directs the signal to the correct section of the cerebral cortex.
The thalamus allows us to know when we touch something and how it feels, pain and pleasure, as well as temperature.
Smell is the only sensory stimulus that is not passed through the thalamus.
Without the thalamus, we wouldn’t know if a stove was hot or if ice was cold. We wouldn’t be able to understand what our eyes see or what our ears hear.
The hypothalamus is mainly involved in motivational behaviors. We understand that we are hungry, thirsty or tired because of the hypothalamus. It controls our circadian rhythm (sleep cycles) as well as emotions.
The hypothalamus houses the pituitary gland. With this pituitary gland and the hypothalamus, the body produces hormones. These hormones control emotions and sex drive, our mood and temperature regulation.
The hypothalamus is responsible for regulating our body temperature and creating homeostasis. This homeostatic pathway allows us to survive by making small changes that prevent us from freezing or starving. Regardless of changes to external stimulus such as weather, external temperature or diet.
The midbrain is made up of the tectum and the tegmentum. Together these work with the thalamus and hypothalamus to control alertness, hearing, vision, temperature control, emotion and sleep cycles.
The tectum has two primary functions: processing visual stimuli and auditory processing stimuli.
The tectum controls eye movement and processes the optical signals, routing them to the cerebral cortex for interpretation. It also processes the signals sent in by our ears and allows us to understand and recognize auditory signals into sounds and words.
The tegmentum works in conjunction with the hypothalamus to maintain homeostasis and reflexive pathways. These paths allow us to regulate our body temperature and redirect changes in our body to ensure we survive.
Along the reflexive pathways, the tegmentum ensures we do not have any unwanted muscle movements by sending inhibitory signals to the thalamus.
The hindbrain is made up of 3 main sections: cerebellum, pons and the medulla oblongata. The primary function of the hindbrain is to regulate and control involuntary actions such as breathing and heartbeat.
The cerebellum is responsible for the coordination of movement, balance and posture. The cerebellum takes in signals sent from the spinal cord and allows us to fine tune motor skills. We can grasp and sit and stand because of the cerebellum.
The cerebellum does not initiate movement but instead controls the precision of fine movements, compound movements and timing.
The pons is a signal super-highway. It connects the upper and lower portions of the brain and acts as a traffic cop for the incoming and outgoing signals.
Aside from its main attribute of brain communication, it also allows us to dream. The pons is responsible for our rapid eye movement (REM) sleep cycle, where we subconsciously dream.
Without the pons, our brains wouldn’t function as no signals would be sent or received.
The medulla oblongata (also called simply the medulla) is responsible for the clear majority of involuntary functions.
The medulla helps signals pass to and from the spinal cord and the thalamus. Moreover, it oversees our respiration, heart rhythm, blood vessel function, digestion, and even sneezing and swallowing.
Without the medulla oblongata, we wouldn’t live. We wouldn’t be able to breathe without thinking about it and our hearts would stop when we went to sleep.
It Just Works
Every section of the brain has a job to do. While each section is an independent work horse allowing us to do everything we need to do as well as understanding the world around us, they also work together.
One section couldn’t function without the other. Working in tandem as well as individually allows us to function, reason, think, learn, eat, digest and breathe. Our brain is an amazing and complex system. We couldn’t live without it.