Biopsychology As A Neuroscience PDF

BIOPSYCHOLOGY AS A NEUROSCIENCE (CHAPTER 1) Neuroscience is the study of the nervous system - from structure to function, development to degeneration, in health and in disease Origin of Biopsychology...

BIOPSYCHOLOGY AS A NEUROSCIENCE (CHAPTER 1) Neuroscience is the study of the nervous system - from structure to function, development to degeneration, in health and in disease Origin of Biopsychology Biological Tradition - Sigmund Freud, behavior is determined by sexual and aggressive drives - Erik Erikson - development follows the epigenetic principle according to a predetermined rate Origin of Biopsychology What is Biopsychology? Hans Eysenck's Biologically Based Factor - also called physiological psychology is the Theory scientific study of the biology of behavior. - Personality has three dimensions: -denotes a biological approach to the study of Extaversion, Neuroticism, Psychoticism. psychology. They are largely inherited rather than learned Extraversion - cortical arousal and sensory Origin of Biopsychology thresholds Pre-Biological Explanations Neuroticism - diathesis-stress model - In the past, behavior had been explained as a Psychoticism - predisposition to stress that product of supernatural or natural elements develops into psychological illness Origin of Biopsychology Origin of Biopsychology Psychological Tradition David Buss' Evolutionary Theory of - Insanity was a natural phenomenon, caused by Personality mental or emotional stress - Personality is shaped by evolutionary - Nicholas Oresme, argued that depression was experiences in adaptation problems (survival & a result of "bizarre behaviors" reproduction) and their mechanisms (solutions) Physical Mechanisms - physiological organs Origin of Biopsychology and systems that evolved to solve problems of Biological Tradition survival - Hippocrates, Father of Western Medicine, Physiological Mechanisms - internal and explained that hysteria is caused by the uterus specific cognitive, motivational, and personality - Galen adopted the ideas of Hippocrates systems that solve adaptation problems creating the humoral theory of disorders. (Attraction - dominance, Trust - dependability, Intimacy - love)  -These variables are expected to change as a Origin of Biopsychology result of an experimental manipulation of the - It did not become a major neuroscientific independent variable. discipline until the 20th century - The Organization of Behavior (1949) by Confounding Variable Donald O. Hebb - is an outside influence that changes the effect - learning based on conjunctures on neural of a dependent and independent variable. networks and synapses being able to strengthen - This extraneous influence is used to influence or weaken over time the outcome of an experimental design. - is an extra variable entered into the equation 3 Major Dimensions of Psychological that was not accounted for. Research 1. Human or non-human subjects Conditions 2. Formal experiments or non-experimental -Designed by the experimenter under which the studies subjects will be tested. 3. Pure or applied WITHIN-SUBJECTS DESIGN 1.1 Human Subjects -all participants are exposed to every treatment Advantages or condition. -​ They can follow instructions -​ They can report their subjective Carryover Effect experiences - is a type of practice effect that occurs because -​ Humans are often cheaper the results from one test influences another. 1.2 Non-Human Subjects (Whenever subjects perform in more than one Non-Human Subjects Advantages condition as they do in within-subject designs) -​ The brains and behavior of non-human there is a possibility of carryover effects. subjects are simpler than those of human subjects. Comparative approach -​ the study of biological processes by comparing different species. -​ Fewer ethical constraints on the study of laboratory species than on the study of humans. 2.1 Experiments -Is the method used by scientists to study causation - to find out what causes what. BETWEEN-SUBJECTS DESIGN > A different group of subjects is tested under Independent Variable each condition. - the variable that is controlled by the > The basic idea behind this type of study is that experimenter by administering treatments. participants can be part of the treatment group or the control group, but cannot be part of both. Dependent Variable > A between subjects design is a way of A. Physiological Psychology avoiding the carryover effects that can plague -Study of the neural mechanisms of behavior by within subjects design. manipulating the nervous systems of non-human subjects in controlled experiments. A. Quasi-experimental Studies - studies of groups of subjects who have been B. Psychopharmacology exposed to the conditions of interest in the real -Study of the effects of drugs on the brain and world. behavior. - These studies have the appearance of -The goal is develop therapeutic drugs or experiments, but they are not true experiments reduce drug abuse because potential confounded variables have no been controlled or randomly selected. C. Neuropsychology -Study of psychological effects of brain damage B. Case Study in human patients. - Studies that focus on a single case or subjects. - Provide a more in-depth picture that that D. Psychophysiology provided by an experiment or -Study of the relation between physiological quasi-experimental study. activity and psychological processes in human Disadvantage of Case Study subjects by noninvasive physiological recording. > Generalizability - the degree to which the result can be applied to other cases. E. Cognitive Neuroscience -study of the neural mechanisms of human 3.1 Pure Research cognition, largely through the use of functional -Is research motivated primarily by the curiosity brain imaging. of the researcher. - It is done solely for the purpose of acquiring Types of Brain Imaging knowledge. 1. Functional Magnetic Resonance Imaging (fMRI) - can be used to produce activation maps 3.2 Applied Research showing which parts of the brain are involved in -Is research intended to bring about some direct a particular mental process. benefit to humankind. 2. Computed Tomography (CT) Scan - builds up a picture of the brain based on the differential Six Major Divisions of absorption of X-rays. Biopsychology 3. Positron Emission Tomography (PET) - A. Physiological Psychology uses trace amounts of short-lived radioactive B. Psychopharmacology material to map functional processes in the C. Neuropsychology brain. D. Psychophysiology 4. Electroencephalography (EEG) - is the E. Cognitive Neuroscience measurement of the electrical activity of the F. Comparative Psychology brain by recording from electrodes placed on the scalp  THE CASE OF THE MAN WHO FELL F. Comparative Psychology OUT OF BED - study of the evolution, genetics, and The patient felt fine when he woke, until he adaptiveness of behavior, largely through the use touched the thing in bed next to him. It was a of the comparative method. severed human leg, all hairy and still warm! At first, the patient was confused. Then, he figured Chapter 2 it out. One of the nurses must have taken it from EVOLUTION, GENETICS, AND the autopsy department and put it in his bed as a EXPERIENCE joke. Some joke; it was disgusting. There is a tendency in the scientific field to think So, he threw the leg out of the bed, but about behavior in terms of dichotomies is somehow, he landed on the floor with it attached illustrated by two kinds of questions: to him. The patient became agitated and (1) Is it physiological, or is it psychological? desperate, and Dr. Sacks tried to comfort him 2) Is it inherited, or is it learned? and help him back into the bed. Making one last effort to reduce the patient's confusion, Sacks PHYSIOLOGICAL OR asked him where his left leg was, if the one PSYCHOLOGICAL (Original meaning of attached to him wasn't it. Turning pale and terms such as psyche) looking like he was about to pass out, the patient The dichotomy rose to prominence in the replied that he had no idea where his own leg Western world after the Medieval Ages was it had disappeared. Much of the scientific knowledge that accumulated during the Renaissance was at odds (ASOMATOGNOSIA- awareness part of the with Church dictates. body, which cannot detect a part of the body) However, the conflict was resolved by the prominent French philosopher René Descartes 2. Some nonhuman species, particularly primate René Descartes argued that physical matter species, possess abilities that were once assumed (the brain) could be observed scientifically, but to be purely human, such as self-awareness that the mind (soul) has no physical substance and is thus under the scope of religion INHERITED OR LEARNED? Cartesian dualism was sanctioned by the For centuries, scholars have debated whether church and and so, the idea that the human brain humans and other animals inherit their and the mind are separate entities became even behavioral capacities or acquire them through more accepte learning. Commonly referred to as the nature-nurture issue THE PROBLEM WITH DICHOTOMIES The majority of early North American There are two lines of evidence against psychologists were committed to the nurture physiological-or-psychological thinking: side of the issue John B. Watson, father of 1.)​ Complex psychological changes can behaviorism “Give me a dozen healthy infants, be produced by damage to, or well-formed, and my own specified world to stimulation of parts of the brain bring them up in and I'll guarantee to take any ​ The Case of the Man Who Fell Out of one at random and train him to become any type Bed of specialist I might select doctor, lawyer, artist, merchant-chief and, yes even beggar-man and thief.”  Repeated cycles of this process lead to evolution of the species that are better adapted to INHERITED OR LEARNED? surviving and reproducing in their particular Coinciding with North Americas experimental environmental niche psychology was European ethology, which focused on instinctive behaviors THE PROBLEM WITH DICHOTOMIES It was changed after it was argued that behaviour always develops under the combined control of both nature and nurture o It is better to think of it as genetics and experience interacting rather than a dichotomy BEHAVIORAL DEVELOPMENT Ontogeny: Development of individuals over their life span Phylogeny: Evolutionary development of species through the ages EVOLUTION MECHANISMS OF BEHAVIOR Modern biology began in 1859 with the Social Dominance: Males of a species often publication of Charles Darwin's On the Origin of establish a hierarchy of social dominance, Species where he described his theory of sometimes through combat. The dominant male evolution usually copulates more than lower-ranked males. Courtship Display: The male usually signals THREE OF DARWIN'S SUPPORTING to the female to elicit a response, though EVIDENCE copulation may fail if one of the pair fails to re 1.​ He documented the evolution of fossil appropriately to the signal records through recent geological layers 2.​ He described striking structural BEHAVIORAL DEVELOPMENT similarities among living species, which Robert Tryon theorized that behavioral traits suggested that they had evolved from can be selectively bred common ancestors He experimented with rats by teaching them 3.​ He pointed to the major changes that how to run a maze had been brought about in domestic He mated the males and females that entered plants and animals by programs of incorrect alleys least frequently (maze-bright) selective breeding and he mated the males and females that entered EVOLUTION incorrect alleys most frequently (maze-dull) Evolution occurs through natural selection: By the 8th generation, the worst of the heritable traits that are associated with high rates maze-bright strain made fewer errors than the of survival and reproduction are the most likely best of the maze-dull strain ones to be passed on to future generations GENETICS OF HUMAN TRANSVERSE PLANE- DIVIDES THE PSYCHOLOGICAL BODY INTO SUPERIOR AND INFERIOR DIFFERENCES PARTS. All human traits are highly heritable Being raised in different family environments NERVOUS SYSTEM contributes little to the diversity of behavioral Coordinates all activities of the body traits. Enables the body to responds and adapts to A Minnesota study of twins had results that changes showed that even if monozygotic twins were raised in different family environments, they CELLS OF THE NERVOUS SYSTEM were substantially more like one another than ANATOMY OF NEURONS fraternal twins NEURONS Are cells that are specialized for the reception, BEHAVIORAL DEVELOPMENT conduction, and transmission of electrochemical Phenylketonuria (PKU): Neurological signals. disorder born from a genetic mutation. Low levels in the amino acid phenylalanine can lead EXTERNAL ANATOMY OF NEURONS to intellectual disability if untreated. NUCLEUS - contains the cell's genetic material Was discovered by the Norwegian dentist CELL BODY - also called the soma, provides Ivar Asbjorn Folling when he noticed that the energy, maintains structure, and contains genetic urine of his mentally retarded children had a information. peculiar odor (samples of their urine showed DENDRITE - are projections from the cell high levels of phenylpyruvic acid) body. The main function of dendrites is to receive information from other ANATOMY OF THE NERVOUS SYSTEM neurons, AXON - long, thin nerve fiber that transmits STANDARD ANATOMICAL POSITION electrical impulses away from a neuron's cell It refers to the specific body orientation used body when describing an individual's anatomy. It MYELIN SHEATH - a fatty layer that consists of the body standing upright and facing surrounds and Insulates nerve cells, forward with the legs parallel to one another. NODE OF RANVIER - are gaps in the myelin The upper limbs, or arms, hang at either side and sheath that regenerate action potentials along the palms face forward. axons, allowing for faster and more efficient communication. PLANES OF THE BODY action potential is a rapid change in the voltage These are imaginary reference points that across a cell membrane divide the body into various sections in order to AXONTERMINAL - the ends of axons which help describe relative anatomy. transmit messages to other cells via use of SAGITTAL PLANE- DIVIDES THE BODY neurotransmitters at synapses INTO RIGHT AND LEFT PARTS. CORONAL PLANE- DIVIDES THE BODY INTO ANTERIOR AND POSTERIOR PARTS. Classes of Neurons Glial cells are the most abundant cell types in the central nervous system. UNIPOLAR NEURON TYPES OF GLIAL CELL A neuron with one process extending from its Oligodendrocytes - their main functions are to cell body. provide support and insulation to axons in the Only occurs in invertebrate glands and central nervous system. muscles. Schwann cells - any of the cells in the peripheral nervous system that produce the myelin sheath around neuronal axons. They guide axonal regeneration (regrowth) after damage PSEUDO-UNIPOLAR NEURON The nerve process extending from the cell body splits into two branches or axons. Sensory neurons BIPOLAR NEURON has two distinct structures extending from the cell body. One is an axon, and the other is a GENERAL LAYOUT OF THE NERVOUS dendrite. SYSTEM olfactory epithelium, retina, and certain nerves within the ear MULTIPOLAR NEURON A neuron with more than two process extending from its cell body Are present throughout a person's CNS, including the brain and associated nerves in the autonomic nervous system GLIAL CELLS Found throughout the nervous system The glial cells surround neurons and provide support for and insulation between them. CENTRAL NERVOUS SYSTEM (CNS) parts of the brain, and sensations such as Division of the nervous system that is located hearing, taste, and balance. within the skull and spine CEREBELLUM - receives information from the integrating and control center of the the sensory systems, the spinal cord, and other nervous system parts of the brain and then regulates motor movements. 1. BRAIN Part of the CNS that is located in the skull Controls all major body function the organ inside the head that controls thought, memory, feelings, and activity FIVE MAJOR DIVISIONS OF THE BRAIN MIDBRAIN a small but important part of the brain that connects the forebrain and hindbrain MESENCEPHALON (MIDBRAIN) Is a portion of the central nervous system associated with vision, hearing, motor control, sleep/wake, arousal and temperature regulation. TWO DIVISIONS OF MESENCEPHALON HINDBRAIN TECTUM -dorsal (top) part of the midbrain. a region of the brain that controls many vital ​ -INFERIOR COLLICULI - is functions, including breathing, heartbeat, and involved in auditory processing. motor coordination ​ -SUPERIOR COLLICULI - is involved in visual function and control MYELENCEPHALON (MEDULLA) of eye movements. The most posterior division of the brain is TEGMENTUM - is the division of the composed largely of tracts carrying signals mesencephalon ventral (lower) to the tectum. It between the rest of the brain and the body. promotes cardiorespiratory functions and Medulla Oblongata helps control vital airway-protective reflexes processes like your heartbeat, breathing and blood pressure. METENCEPHALON FOREBRAIN controls body temperature, Part of the hindbrain that differentiates into the reproductive functions, eating, sleeping, and the pons and the cerebellum display of emotions. PONS -. It is involved in the control of DIENCEPHALON breathing, communication between different is situated between the telencephalon and the midbrain. Composed of two structures: THALAMUS responsible for the integration of complex AND HYPOTHALAMUS sensory and neural functions and the initiation and coordination of voluntary activity in the body. THALAMUS Is a large mass of grey matter in the dorsal part of the diencephalon of the brain. relays motor and sensory signals to the cerebral cortex. It also FRONTAL LOBE regulates sleep, alertness, and wakefulness The frontal lobes make up the largest part of the cortex. - Their central functions are to process information relating to memory, planning, decision making, goal setting, and creativity. -The frontal lobes also contain the primary motor cortex that regulates muscular movements. HYPOTHALAMUS TEMPORAL LOBE It exerts its effects in part by regulating the located on the side of the cerebrum, is release of hormones from the pituitary gland responsible for processing auditory information. which dangles from it on the ventral surface of the brain. It plays an important role in the regulation of several motivated behaviors (e.g., eating, sleep, and sexual behavior) PARIETAL LOBE - Located at the top of the brain in the cerebrum are responsible for the sense of touch, and they help to determine body position and integrate visual information. -The parietal lobes have anterior (front) and TELENCEPHALON (CEREBRUM) posterior (rear) sections. The largest division of the human brain.  HIPPOCAMPUS OCCIPITAL LOBE is the brain structure responsible for memory are primarily concerned with processing visual of the immediate past. information. FORNIX The occipital lobe also is known as the visual - is a C-shaped bundle of nerve fibers in the cortex. brain that acts as the major output tract of the hippocampus. - Damage to the fornix has been associated with anterograde amnesia-inability to create new memories. CEREBRAL CORTEX The outermost layer of the brain contains gray matter. Responsible for many higher order functions like language and information processing. CINGULATE CORTEX It is involved in processing emotions and behavior regulation. It also helps to regulate autonomic motor function. LIMBIC SYSTEM Is involved in the regulation of motivated and emotional behaviors process your memory, thoughts and motivations, then tell your body how to respond. BASAL GANGLIA responsible primarily for motor control, as well as other roles such as motor learning, executive functions and behaviors, and emotions. AMYGDALA is involved in the control of emotion, survival instincts and memory. The amygdala's function is to assess the CAUDATE NUCLEUS harmfulness of sensory inputs. Means "tail-like” The caudate nucleus is a C-shaped structure.  It's responsible for processing visual The spinal cord is protected by the vertebrae, information, movement, and memory. which are bones running down your back, and also by cerebral spinal fluid, which help to PUTAMEN cushion the nerve tissue the outer part of the nucleus of the brain. is involved in motor learning, speech articulation, language functions, reward, cognitive functioning, and addiction TWO DIFFERENT AREAS OF SPINAL CORD GRAY MATTER STRIATUM WHITE MATTER decision making functions, such as motor control, emotion, habit formation, and reward. GRAY MATTER is a tissue in the brain and spinal cord that processes and interprets information. It plays a significant role in mental functions, memory, emotions and movement. is composed largely of unmyelinated axons. GLOBUS PALLIDUS control conscious and proprioceptive movements. (your body's ability to sense movement, action, and location) 3 LAYERS OF MENINGES Are layers of tough and connective tissue that protect and cover the brain and spinal cord 2. SPINAL CORD Is a long, thin bundle of nervous tissue and support cells connected to the brain and located along your back and neck Receives and transmits electrical signals throughout the entire body and then back to the brain MENINGES, VENTRICLES, AND CENTRAL CANAL CEREBROSPINAL FLUID also known as ependymal canal, is the cerebrospinal fluid-filled space that runs longitudinally through the length of the entire spinal cord. The central canal is continuous with the ventricular system of the brain. 3 LAYERS OF MENINGES A.DURA MATER - the thickest and outermost CEREBROSPINAL FLUID (CSF) of the three meninges surrounding the brain and is a clear, colorless body fluid found in the spinal cord. brain and spinal cord. Fills the subarachnoid space, the central canal B. ARACHNOID MATER - Spider weblike of the spinal cord, and the cerebral ventricles of membrane - the middle of the three membranes the brain covering the brain and spinal cord. It is separated from the pia mater by the “subarachnoid cavity" which is filled with "cerebrospinal fluid." C.PIA MATER - is the meningeal envelope that firmly adheres to the surface of the brain and spinal cord. It is a very thin membrane composed of fibrous tissue covered on its outer surface by a sheet of flat cells BLOOD-BRAIN BARRIER Composed of tightly packed cells of the brain's CEREBRAL VENTRICLES blood vessel walls Are the four large internal chambers of the Impedes the passage of many toxic substances brain; the two lateral ventricles, the third from the blood into the brain ventricle, and the fourth ventricle are responsible for the production, transport and removal of cerebrospinal fluid, B. PERIPHERAL NERVOUS SYSTEM (PNS) is the division of the nervous system containing all the nerves that lie outside of the central nervous system (CNS).  The primary role of the PNS is to connect the CNS to the organs, limbs, and skin. TWO DIVISIONS OF PNS Somatic Nervous System (SNS) Autonomic Nervous System (ANS) 1. SOMATIC NERVOUS SYSTEM (SNS) "VOLUNTARY" The somatic nervous system derives its name from the Greek word soma, which means "body." Is the part of the PNS that responsible for carrying sensory and motor information to and B. PARASYMPATHETIC NERVOUS from the central nervous system. SYSTEM It is composed of afferent and efferent nerves Are those autonomic motor nerves that project from the brain and sacral (lower back) region of A. AFFERENT NERVES the spinal cord Also known as sensory neurons Regulates the rest or digest response Carry sensory signals from the skin, skeletal muscles, joints, eyes, ears, and so on, to the central nervous system B. EFFERENT NERVES Also known as motor neurons Carry motor signals from the central nervous system to the skeletal muscles. 2. AUTONOMIC NERVOUS SYSTEM (ANS) "INVOLUNTARY" is the part of the peripheral nervous system that regulates the body's internal environment. It is composed of afferent nerves that carry sensory signals from internal organs to the CNS FUNCTIONS OF SYMPATHETIC AND and efferent nerves that carry motor signals from PARASYMPATHETIC SYSTEMS the CNS to internal organs. SYMPATHETIC SYSTEM TWO KINDS OF EFFERENT NERVES ​ Stimulate, organize, and mobilize UNDER ANS energy resources in threatening A.Sympathetic Nervous System situations (makes you alert) ​ Sympathetic changes are indicative B. Parasympathetic Nervous System (makes indicative of psychological of arousal you calm) PARASYMPATHETIC SYSTEMS ​ Act to conserve energy A. SYMPATHETIC NERVOUS SYSTEM ​ Indicative of psychological relaxation Are those autonomic motor nerves that project from the CNS in the lumbar (small of the Neural Conduction and Synaptic back) and thoracic (chest area) regions of the Transmission How Neurons Send and Receive spinal cord Signals Regulates the flight or fight responses. This chapter introduces you to their function These neurons make a particular chemical called how neurons conduct and transmit dopamine, which they deliver to another part of electrochemical signals through your nervous the brain, known as the striatum. As the cells of system the substantia nigra die, the amount of dopamine ​ how signals are generated in resting they can deliver goes down. The striatum helps neurons; control movement, and to do that normally, it ​ The signals are conducted through needs dopamine. neurons and transmitted across synapses to other neurons. RESTING MEMBRANE POTENTIAL ​ how drugs are used to study the relation between synaptic transmission and behavior The Lizard, a Case of Parkinson s Disease Thave become a lizard, he began. A great lizard frozen in a dark, cold, strange world. His name was Roberto Garcia d Orta. He was a tall thin man in his sixties, but most like patients with parkinson's disease he appeared to be much older than his actual age. Not many years before, he had been an active, vigorous businessman. Then it happened not all at once, not suddenly, but slowly, subtly, insidiously. Now he turned Recording the Membrane Potential like a piece of granite, walked in slow shuffling Position the tip of one electrode inside the steps, and spoke in a monotonous whisper. neuron and the tip of another electrode outside the neuron in the extracellular fluid. What had been his first symptom? A tremor. The intracellular electrodes are called microelectrodes; their tips are less than Had his tremor been disabling? No, he said. My one-thousandth of a millimeter in diameter. hands shake worse when they are doing nothing When both electrode tips are in the at all a symptom called tremor-at-rest. extracellular fluid, the voltage difference between them is zero. The other symptoms of Parkinson s disease are When the tip of the intracellular electrode is not quite so benign. They can change a vigorous inserted into a neuron, a steady potential of man into a lizard. These include rigid muscles, about 70 millivolts (mV) is recorded a marked poverty of spontaneous movements, In its resting state, with the 70 mV charge built difficulty in starting to move, and slowness in up across its membrane, a neuron is said to be executing voluntary movements once they polarized. have been initiated. The membrane potential is the difference in The term reptilian stare is often used to describe electrical charge between the inside and the the characteristic lack of blinking and the widely outside of a cell. opened eyes gazing out of a motionless face, a set of features that seems more reptilian than Resting Membrane Potential human. Truly a lizard in the eyes of the world Neurons have a selectively permeable membrane What was happening in Mr. d Orta s brain? A During resting conditions membrane is; small group of nerve cells called the substantia Permeable to Potassium (K+) (channels are nigra (black substance) were unaccountably open) dying. Impermeable to Sodium (Na+) (channels are closed) lonic Basis of the Resting Potential Four kinds of ions that contribute RII significantly to the resting potential: The resting potential is -70 millivolts ​ sodium ions (Na*), The resting potential exist because positively ​ potassium ions (K*), and negatively charged ions are distributed ​ chloride ions (CI+), unequally on the two sides of the neural ​ Negatively charged protein ions. membrane: the concentration of Na+ and CI-are higher outside the neuron, and the concentration Synaptic Transmission: Chemical of the K+ and various negatively charged Transmission of Signals among Neurons proteins are higher inside the neuron Synapses: The places where neurons connect and communicate with each other Resting Membrane Potential Diffusion force pushes K+ out (concentration gradient) This creates a positively charged extracellular Neurotransmitters: Neurotransmitter molecules space are endogenous chemicals that allow neurons to Electrostatic force pushes K+ in communicate with each other throughout the Thus, there is a dynamic equilibrium with zero body net movements of ions The resting membrane potential is negative Release of Neurotransmitter Molecules EXOCYTOSIS: is the process of Two (2) factors that act to distribute ions neurotransmitter release. When a neuron is at equally throughout the intracellular and rest, synaptic vesicles that contain extracellular fluids of the nervous system small-molecule neurotransmitters tend to RANDOM MOTION: The ions in neural congregate near sections of the presynaptic tissue are in constant random motion, and membrane that are particularly rich in particles in random motion tend to become voltage-activated calcium channels evenly distributed because they are more likely to move from areas of high concentration to areas of low concentration than vice versa. ELECTROSTATIC PRESSURE: Any accumulation of charges, positive or negative, in one area tends to be dispersed by the repulsion among the like charges in the vicinity and the attraction of opposite charges concentrated elsewhere. Reuptake, Enzymatic Amino Acid Neurotransmitters Degradation, and Recycling GLUTAMATE - excitatory neurotransmitter Reuptake is the process in which the majority important to memory, cognition, and mood of neurotransmitters, once released, are almost regulation. High levels = Parkinson's immediately drawn back into the presynaptic Alzheimer's; Low Levels = learning buttons by transporter mechanisms. and memory issues Other neurotransmitters are degraded (broken GAMMA-AMINOBUTYRIC ACID apart) in the synapse by the action of enzyme (GABA) - slows down your brain by blocking proteins that stimulate or inhibit biochemical specific signals in your central nervous system. reactions without being affected by them. Low levels = mood disorders, anxiety, schizophrenia, autism Glial Function and Synaptic Transmission Monoamine Neurotransmitters Astrocytes have been shown to release They are subdivided into two groups, chemical transmitters, to contain receptors for catecholamines and indolamines neurotransmitters, to conduct signals, and to DOPAMINE - plays a role as a "reward participate in neurotransmitter reuptake center" and in many body functions, including Gap junctions are narrow spaces between memory, movement, motivation, mood, attention adjacent neurons that are bridged by fine tubular and more. channels, called connexins, that contain EPINEPHRINE - also known as adrenaline, cytoplasm plays an important role in your body's "fight-or-flight" response. NOREPINEPHRINE - increases alertness, arousal and attention and affects your sleep-wake cycle, mood and memory SEROTONIN - regulates your mood. It's often called your body's natural "feel good" chemical. Neurotransmitters When serotonin is at normal levels, you feel Chemical messengers that allow signals to more focused, emotionally stable, happier and cross synapses to transmit information from a calmer. nerve cell or neutron to a target cell Coordinate behavior by stimulating an action Acetylcholine or inhibiting an impulse It is created by adding an acetyl group to a choline molecule. Acetylcholine is the neurotransmitter at neuromuscular junctions, at many of the synapses in the autonomic nervous system, and at synapses in several parts of the central nervous system. Acetylcholine is a neurotransmitter that plays a role in memory, learning, attention, arousal and involuntary muscle movement. Medical conditions associated with low acetylcholine levels include Alzheimer's disease and myasthenia gravis. Unconventional Neurotransmitters These neurotransmitters are produced in the neural cytoplasm and immediately diffuse through the cell membrane into the extracellular fluid and then into nearby cells SOLUBLE GAS- includes nitric acid and carbon monoxide. ENDOCANNABINOIDS- synthesized from fatty compounds in the cell membrane; they tend to be released from the dendrites and cell body, an anandamide Neuropeptides: are small proteinaceous substances produced and released by neurons through the regulated secretory route and acting on neural substances. Pituitary peptides contains neuropeptides that were first identified as hormones released by the pituitary; a Hypothalamic peptides contains neuropeptides that were first identified as hormones released by the hypothalamus; Brain gut peptides contains neuropeptides that were first discovered in the gut. Opioid peptides contains neuropeptides that are similar in structure to the active ingredients of opium, Miscellaneous peptides is a catch-all category that contains all of the neuropeptide transmitters that do not fit into one of the mother four categories.