University:
College
Course:
College Psychology
Academic year:

2021
Views:

416

Pages:

37
Author:

Febelli4n

Biological Psychology Essential Task 3-1: Identify the basic parts of the neuron (dendrites, cell body, axon, terminal buttons, synaptic vesicles, and receptor sites) Evolutionary Endocrine System We are here Building Blocks Biological Psychology Genetics Neurons Nervous System Central Nervous System Peripheral Nervous System Motor Brain Brain Imaging Spinal Cord Autonomic Sympathetic Neurotransmitters Sensory Somatic Parasympathetic Essential Task 3-1: Outline • Biological Psychology defined – Principles of Bio Psych • Basic parts of the neuron – – – – Dendrites (Receptor sites) Cell body Axon (Myelin Sheath and Glial Cells (White vs. Gray Matter) ) Terminal buttons (Synaptic vesicles) • Synapse – – – – Terminal buttons (Synaptic vesicles) Neurotransmitters Synaptic Cleft/Space Receptor Sites Biological Psychology Outline  branch of psychology that studies how the body/physiology influences behavior and mental processes  some biological psychologists call themselves behavioral neuroscientists, neuropsychologists, behavior geneticists, physiological psychologists, or biopsychologists Biological Psychology Outline Principles of Biological Psychology  Everything psychological is simultaneously biological.  The nervous system is complexity built from simplicity.  The brain is both specialized and integrated.  The nervous system is “plastic” (change) especially at early ages of development. Neurons: The Messengers Outline • About 100 billion neurons (nerve cells) in the human brain. Recent estimates put it at about 86 billion. • About 100 trillion connections amongst these neurons. • Neurons have many of the same features as other cells – Nucleus – Cytoplasm – Cell membrane • What makes neurons unique is their shape and function Brain Activity Map Project Outline • Started in 2013 this project is going to attempt to map the connection of every neuron in a human brain by 2023 I. STRUCTURE OF THE NEURON Types of Neurons Outline • Sensory neurons – Carry information from sensory systems to the brain – Also referred to as afferent neurons • Motor neurons – Carry information from the brain to muscles and glands – Also referred to as efferent neurons • Interneurons – Carry information between other neurons Structure of Neurons Outline • Dendrites – Carry information to the cell body from other neurons • Cell Body (Soma) – Contains nucleus – Soma means “Body” • Axon – Carries information to the next cell • Myelin Sheath – Insulates the axon and speeds up the neural impulse • Terminal button – Enlarged area at the end of an axon that send out information Outline Neuron Outline Neural Communication Outline The Synapse Outline • The synapse – Composed of the terminal button of one neuron, the synaptic space, and the dendrites or cell body of the receiving neuron • Terminal button – Enlarged area at the end of an axon • Synaptic space (synaptic cleft) – Tiny gap between neurons • Receptor Sites – Sites on the dendrite of the receiving neuron where neurotransmitters bind fitting like keys into specially designed locks. Chemical Transmission Between Neurons Outline • Synaptic vesicles release neurotransmitters that bind to receptor sites. – Sacs in terminal button that release chemicals into synaptic space – Chemicals released by synaptic vesicles – Sites on the dendrite of the receiving neuron where neurotransmitters bind fitting like keys into specially designed locks. Outline Chemical Transmission BETWEEN Neurons Outline Glial Cells Outline • • • • • Cells that insulate and support neurons Create the myelin sheath Remove waste products Provide nourishment Prevent harmful substances from entering the brain • Forms white matter in the brain helping communication across the brain • Gray matter is un myelinated brain tissue. White and Gray Matter II. NEUROTRANSMITTERS Neurotransmitters Outline • Neurotransmitters (chemicals) released from the sending neuron that travel across the synaptic cleft and bind to receptor sites on the receiving neuron, thereby influencing it to generate an action potential. • Neurotransmitter is NOT a hormone! Chemical Communication Outline Terminal button Enlarged area at the axon terminal Synaptic vesicles Sacs in the terminal button that release chemicals called neurotransmitters into the synaptic space Synaptic space (synaptic cleft) - Tiny gap between neurons Receptor sites Location on receptor neuron where neurotransmitters can bind. Neurotransmitters fit like chemical keys in chemical locks. Outline Lock and Key Mechanism 2 Categories of neurotransmitters: Excitatory and Inhibitory Outline Excitatory •The key fits and ‘opens’ the receiving neuron. •Activation of the receptor causes depolarization of the membrane and promotes an action potential (firing of neurons) in the receiving neuron. Inhibitory •The key fits in but only stops any other keys. •Activation of the receptor causes hyperpolarization and depresses action potential generation. (slows or stops firing) Drugs that excite a neuron are called Agonists Outline Agonist excites!!! Drugs that inhibit a neuron are called antagonists Outline Antagonists stops!!! Reuptake Outline • Neurotransmitters in the synapse are reabsorbed into the sending neurons through the process of reuptake. This process applies the brakes on neurotransmitter action. *Neurotransmitters are taken back Selective Serotonin Reuptake Inhibitors (SSRI) Outline Citalopram (Celexa) Escitalopram (Lexapro) Fluoxetine (Prozac) Paroxetine (Paxil, Pexeva) Sertraline (Zoloft) Some Well-Known Neurotransmitters • Acetylcholine (ACh) – Released at the neuromuscular junction (activates muscles) – Plays an important role in arousal and attention – Oversupply leads to spasms – Undersupply is linked to Alzheimer’s disease and paralysis • Dopamine – Affects neurons associated with pleasure and voluntary movement (muscle control) – Plays a role in learning, memory, and emotions – Undersupply leads to Parkinson’s Disease – Oversupply leads to Schizophrenia Dopamine Drugs like cocaine and amphetamines triggers large amounts of dopamine production. The over production and the loss of production of dopamine is what causes addiction in these drugs. Some Well-Known Neurotransmitters • Serotonin – – – – – Found throughout the brain Appears to sets an “emotional tone” Affects mood, hunger, sleep, and arousal Low serotonin levels are implicated in depression Some antidepressant drugs raise serotonin • Norepinephrine – Helps control alertness and arousal – Alerts body of danger – Undersupply are implicated in ADHD and depression Serotonin Key ingredient in ecstasy targets over production of serotonin. Some Well-Known Neurotransmitters • GABA (Gamma-aminobutyric acid) – Inhibitory neurotransmitter – involved in memory, movement, and sleep – linked to seizures, tremors, Huntington's disease, and insomnia • Endorphins – Reduce pain by inhibiting or “turning down” neurons that transmit pain information – Endures pain (pain reliever) – “runner’s high” – No established problems Other Neurotransmitters you may need to know • Epinephrine – Adrenaline – Fight or flight response – when you are in an emergency! • Glutamate – Primary excitatory neurotransmitter – Long-term memory