Module 2: Biological Psychology
2.1. Nervous system and brain

The nervous system is a complex network of nerve cells that allows us to perceive external signals, process information, and respond to our environment.

Let's imagine the nervous system as a communication network consisting of two main components: the central nervous system (CNS) and the peripheral nervous system (PNS).

The central nervous system consists of the brain and spinal cord. The brain is an organ that plays a key role in regulating mental processes. It is responsible for thinking, memory, experiences and behavior. The spinal cord, in turn, transmits signals between the brain and the rest of the body.

The peripheral nervous system includes specialized nerve cells called neurons that transmit information between the central nervous system and the body's organs. The peripheral nervous system is divided into two components: somatic and autonomous.

The somatic nervous system controls voluntary movement and perception of sensations from the environment. It allows us to move freely, react to different situations, and perceive different stimuli, such as sounds, smells, and so on.

The autonomic nervous system regulates the functions of our internal body, which we do not control by our will. It controls our digestion, respiration, heart rate, and other automatic processes. The autonomic nervous system is divided into two components: sympathetic and parasympathetic.

The sympathetic nervous system activates the body in stressful situations or threats. It increases your heart rate, dilates your bronchi, increases your adrenaline, and helps you prepare for a fight or flight.

The parasympathetic nervous system, on the contrary, causes relaxation and recovery of the body. It lowers your heart rate, improves digestion, and promotes muscle relaxation.

So, the nervous system plays a critical role in the functioning of our mental state and behavior. The central nervous system processes information and regulates our thoughts, emotions, and memory. The peripheral nervous system connects the central nervous system to the body's organs, allowing us to respond to our environment and maintain internal homeostasis.

The brain is the most complex organ in our body and is the central part of the nervous system. It consists of billions of nerve cells called neurons and their interconnected networks.

The brain is divided into several parts, each of which performs its own unique functions.

Brain (Hemispheres)

• The brain consists of two hemispheres: the right and the left. They control motor functions and sensory information processing.

• The sexual lobes (hemispheres) are connected by bundles of nerve fibers called the thalamic arches.

The cerebellum:

• The cerebellum is responsible for coordinating movement and maintaining balance.

Brain stem:

• The brainstem connects the brain to the rest of the body.

• It regulates autonomous functions such as breathing and heart activity.

Brain structures:

Neurons

• The main functional units of the brain are neurons.

• Neurons transmit information in the form of electrical impulses.

Synapses

• Synapses are the points of contact between neurons where information is transmitted using neurotransmitters.

Frontal, temporal, temporal-parietal and occipital lobes

• The frontal lobes are involved in planning, making decisions, and controlling behavior.

• The temporal lobes are associated with auditory processing and memory.

• The temporal-parietal lobes are involved in processing tactile information and are located in the upper part of the head.

• The occipital lobes are associated with the processing of visual information.

Limbic system

• The limbic system is responsible for emotions, memory, and motivation.

The brain is an amazing organ, and its structure is complex and interesting. This lecture only briefly touched on the main aspects of its anatomy, but the study of the brain and its functions continues, and this is one of the most exciting research areas in science.