Neuroscience & Behavior PDF

NEUROSCIENCE & BEHAVIOR PSYCH 101 - INTRODUCTION TO PSYCHOLOGY NEURONS Neurons (also called neurones or nerve cells) are the fundamental units of the brain and nervous system, the cells responsible for receiving sensory input from the external world, for sending motor commands...

NEUROSCIENCE & BEHAVIOR PSYCH 101 - INTRODUCTION TO PSYCHOLOGY NEURONS Neurons (also called neurones or nerve cells) are the fundamental units of the brain and nervous system, the cells responsible for receiving sensory input from the external world, for sending motor commands to our muscles, and for transforming and relaying the electrical signals at every step in between. CHAPTER 2  COMMUNICATION BETWEEN SYNAPSES Communication between synapses involves the transfer of signals from one neuron to another. This process is crucial for transmitting information throughout the nervous system. NEUROTRANSMITTERS Neurotransmitters are often referred to as the body's chemical messengers. They are the molecules used by the nervous system to transmit messages between neurons, or from neurons to muscles. Communication between two neurons happens in the synaptic cleft (the small gap between the synapses of neurons). Acetylcholine Endorphins Acetylcholine (ACh) is a neurotransmitter, Endorphins are neurotransmitters released a chemical that carries messages from by the pituitary gland and hypothalamus in your brain to your body through nerve the brain. As natural hormones, they can cells. It's an excitatory neurotransmitter. alleviate pain, lower stress, improve mood, This means it “excites” the nerve cell and and enhance your sense of well-being. The causes it to “fire off the message.” body releases endorphins when you do pleasurable activities such as eating, Medical conditions associated with low exercise, and sex, etc. acetylcholine levels include Alzheimer's disease and myasthenia gravis.  Dopamine Serotonin (small molecule neurotransmitter) Dopamine is often associated with the brain's Primarily regulates mood, emotion, sleep, reward system. It plays a crucial role in and appetite. It contributes to feelings of motivation, pleasure, and reinforcement of well-being and happiness. Often referred to behaviors. It's also involved in regulating as the "feel-good" neurotransmitter, movement, attention, learning, and emotional serotonin is primarily found in the brain, responses. bowels, and blood platelets. Parkinson’s disease is one illness associated Imbalances are linked to conditions like with deficits in dopamine, while depression, anxiety, and irritable bowel schizophrenia is strongly linked to excessive syndrome. amounts of these chemical messengers. THE NERVOUS SYSTEM The nervous system is a complex network of nerves and cells that carry messages to and from the brain and spinal cord to various parts of the body. It is responsible for receiving, processing, and transmitting information throughout the body, allowing us to respond to internal and external stimuli. The nervous system controls everything from basic reflexes to complex behaviors, emotions, and cognitive functions. THE NERVOUS SYSTEM The nervous system is divided into two main parts: Central Nervous System (CNS): The control center of the body, consisting of the brain and spinal cord, responsible for processing and coordinating sensory information and directing responses. PNS (Peripheral Nervous System): Is made up of the Somatic and Autonomic nervous systems. THE ENDOCRINE SYSTEM The endocrine system is made up of glands that make hormones. Hormones are the body's chemical messengers. They carry information and instructions from one set of cells to another. It influences almost every cell, organ, and function of our bodies. The endocrine system plays a role in regulating mood, growth, and development, tissue function, metabolism, and sexual function and reproductive processes. THE ENDOCRINE SYSTEM The major glands that make up human endocrine system include: Hypothalamus - Regulates the pituitary gland and maintains homeostasis Pituitary gland - Controls other endocrine glands and releases hormones that influence growth, metabolism, and reproduction. Thyroid - Regulates metabolism, energy levels, and growth through hormone secretion. Para thyroids - Control calcium levels in the blood and bone health. Adrenal glands - Produce hormones that manage stress, metabolism, and electrolyte balance. Pineal body- Secretes melatonin, which regulates sleep-wake cycles. Reproductive glands- (Ovaries and testes) produce hormones related to reproduction and secondary sexual characteristics. Pancreas - Regulates blood sugar levels by producing insulin and glucagon. THE BRAIN The brain lies within the skull and is shaped like a mushroom.  BRAIN STRUCTURE Grey Matter: Contains neuron cell bodies and neuroglia. It receives and processes information. White Matter: Consists of nerve fibers (axons) that carry impulses to and from grey matter. The brain weighs approximately 1.3 to 1.4 kg. The corpus callosum is a thick band of nerve fibers located beneath the cerebral cortex, connecting the left and right hemispheres of the brain. It facilitates communication and coordination between the two hemispheres, allowing them to work together efficiently. The ventricles are a series of interconnected, fluid-filled cavities within the brain. There are four main ventricles  THE BRAIN The brain is the central organ of the nervous system and is responsible for a wide range of functions, including cognition, emotion, and regulation of bodily processes. It's divided into several key parts: 1. Cerebrum: The largest part of the brain, responsible for higher brain functions like thinking, reasoning, and voluntary movement. It is divided into two hemispheres (left and right) and further into lobes (frontal, parietal, temporal, and occipital). Frontal Lobe: Involved in decision-making, problem-solving, and controlling voluntary movements. Parietal Lobe: Processes sensory information such as touch and temperature. Temporal Lobe: Handles auditory processing and memory. Occipital Lobe: Responsible for visual processing.  THE BRAIN 2. Cerebellum: Coordinates voluntary movements, balance, and posture. 3. Brainstem - The brainstem is a vital part of the brain that connects the cerebrum with the spinal cord. It plays a crucial role in regulating basic life functions and maintaining overall bodily homeostasis. It is composed of three main parts: Midbrain: Manages auditory and visual reflexes. Pons: Relays messages between the cerebrum and cerebellum and controls some functions related to sleep and respiration. Medulla Oblongata: Controls vital functions like heart rate, breathing, and blood pressure. Controls essential autonomic functions such as heart rate, blood pressure, and breathing. Coordinates reflexes like swallowing, coughing, and vomiting.  THE BRAIN 4. Diencephalon: Includes structures like the thalamus and hypothalamus, which are involved in sensory perception, motor control, and homeostasis. The diencephalon acts as a primary relay and processing center for sensory information and autonomic control. Thalamus - acts as a relay station for sensory information. Hypothalamus- regulates homeostasis, including temperature, hunger, thirst, and emotional responses. 5. Limbic System: A group of structures including the hippocampus and amygdala, crucial for emotion, memory, and learning. Hippocampus: Crucial for memory formation. Amygdala: Involved in emotional responses and memory processing The brain is composed of neurons (nerve cells) and glial cells (support cells). Neurons transmit information through electrical and chemical signals, while glial cells support and protect neurons.