Behavioural Neuroscience Flashcards
Neuroscience
The study of how nerves and cells send and receive information from the brain, body, and spinal cord.
Cerebral Cortex
The outermost layer of the brain. Supports cognitive skills, complex emotions, and complex mental activity including your sense of mind and self. Two hemispheres. Each is separated into four sections/lobes.
Neurons
The cellular building blocks of the brain.
Genes
The basic physical and functional units of heredity. Made up of DNA.
Neurodiversity
An appreciation of the range of differences in brain function among individuals.
Nervous System
A network of neurons running throughout your brain and body.
Nerve
A collection of neurons that carries signals from the body to the brain.
Motor Neuron
A neuron that sends signals to make the body take action. Sends messages out to the body’s tissues from the brain.
Sensory Neuron
A neuron that carries information from the outside world and within the body to the brain. Carries messages from sensory organs and tissues to the brain and spinal cord.
Interneuron
A neuron that connects neurons and interprets, stores, and retrieves information about the world, allowing you to make informed decisions before you act (neurons communicate with each other within the brain and spinal cord).
Spinal Cord
The major bundle of nerves, encased in your spine, that connects your body and your brain.
Central Nervous System (CNS)
The system composed of the brain and spinal cord. Information from your body travels to the brain by way of the nerves of your spinal cord.
Peripheral Nervous System (PNS)
The system composed of the nerves outside of the brain and spinal cord. Connects the parts of the body to the brain.
Somatic Nervous System (SNS)
The system that allows us to feel external sensations and control voluntary movement of the body.
Autonomic Nervous System (ANS)
The system that allows us to feel internal sensations from and controls automatic movements of the organs such as heartbeat.
Sympathetic Nervous System
A division of the autonomic nervous system that acts on blood vessels, organs, and glands in ways that prepare the body for action, especially in life-threatening situations (fight-or-flight response).
Parasympathetic Nervous System
A division of the autonomic nervous system that returns the body to a resting state by counteracting the actions of the sympathetic system (rest and digest).
Endocrine System
A network of glands that produces and releases hormones into the bloodstream to regulate the body’s activities. Able to coordinate hormone release with the CNS and PNS, allowing signal exchange from your brain to your body and back again.
Hormones
The blood-borne chemicals that travel through the circulatory system enabling the brain to regulate the body’s activities.
Adrenal Glands
The endocrine glands located on top of the kidneys. They produce a variety of hormones, including adrenaline and cortisol, that are central to the stress response. Are also best known for their role in the fight-or-flight response.
Pituitary Gland
The master endocrine gland located at the base of the brain that in addition to producing its own hormones regulates hormone production in other glands.
3 Main Structures of the Brain
1) Forebrain
2) Midbrain
3) Hindbrain
Neocortex
The evolutionarily newest cerebral cortex that is the largest part of the human brain. Supports complex functions, including language, thought, problem solving, and imagination.
Occipital Lobe
A lobe that runs along the back portion of the head. Contains the primary visual cortex and is largely devoted to vision. Distinct groups of neurons are responsible for detecting shape, colour, movement, and etc. Other parts of the brain are recruited to help put all the information back together into a coherent picture.
Temporal Lobe
A lobe that runs alongside the ears. Contains the primary auditory cortex and is responsible for the ability to hear and understand language. Used for speech production and language. Contains the primary auditory cortex that is used for object and facial recognition (fusiform gyrus).
Parietal Lobe
A lobe that runs alongside the head above and behind the ears. Contains the primary somatosensory cortex, supporting a map of the body’s skin surface and the sense of touch. Used for spatial attention and spatial sense.
Frontal Lobe
A lobe located in the front of the head. Contains the primary motor cortex and a map of the body’s muscles essential for movement and planning. Used for planning, goal making, inhibition, personality, executive functions, and contains the primary motor cortex that controls movement. It is the part of the brain that is considered to make humans different from other animals.
Insular Lobe
The cortex that is insulated by the overlying cortex. Supports the sense of taste and allows perception of the internal organs.
Different Cortexes for the 5 Senses
1) Visual Cortex (seeing)
2) Auditory Cortex (hearing)
3) Gustatory Cortex (tasting)
4) Olfactory Cortex (smelling)
5) Somatosensory Cortex (touching)
Primary Sensory Areas
The first regions of the cerebral cortex to receive signals from a sensory organ via its sensory nerve.
Primary Motor Cortex
The cortex that is responsible for voluntary movements (works with other parts of the brain to coordinate complex movements).
Association Cortex
The cortex that integrates information coming in from the senses with existing knowledge.
Limbic System
A system often associated with emotion. It bridges the older, lower brain regions that regulate the body with the newer, higher brain structures more related to complex mental functions.
Hippocampus
A component of the limbic system crucial for certain aspects of memory, the ability to navigate the environment, and the ability to think about the future. Consolidation of information from short-term to long-term memory and spatial memory (critical for memory).
Amygdala
A component of the limbic system important for registering the emotional significance of events. Controls emotions, emotional behaviour, fear responses, and memory for emotional events (critical for processing the significance of emotional situations and determining which emotion we need to feel at that moment).
Basal Ganglia
A group of interconnected structures that are an evolutionary older subcortical motor system necessary for planning and executing movement. Involved in planning and carrying out movement. Damage to this area of the brain is associated with Parkenson’s Disease.
Thalamus
A subcortical structure deep in the middle of the brain. Communicates information to and from all of the sensory systems except the olfactory (smell) system, regulating alertness and consciousness. Sensory switchboard (relays sensory information to appropriate brain regions). Controls sleep and consciousness.
Hypothalamus
The master controller of the brain and body. Integrates bodily signals with their associated feelings and behaviours. Regulates specific functions including hunger, body rhythms, reward seeking, and aggression. Directly below the thalamus. Responsible for body maintenance ie. homeostasis (thirst, hunger, sex drives, and temperature).
Brainstem
The lowest region of the brain. It sits on top of and is continuous with the spinal cord collecting sensory signals from the body and sending signals down from the brain to create movement and regulate vital function. Where the spinal cord meets the skull. Most fundamental portion of the brain. Controls automatic functions related to survival.
Midbrain
The uppermost region of the brainstem. It includes the tegmentum and substantia nigra, critical for dopamine production. Controls motor movements and reflexes.
Pons
An upper brainstem structure that controls breathing and relays sensations, such as hearing, taste, pain, and balance, to the subcortex and cortex.
Medulla Oblongata/Medulla
A lower brainstem structure that controls autonomic functions, including heart rate and blood pressure, and reflexes like coughing and swallowing.
Reticular Formation
A structure that runs through the brainstem and is connected to many parts of the brain. Plays a central role in arousal and attention.
Cerebellum
A hindbrain structure that supports a variety of functions, including coordination, precision, balance, and accurate timing. Coordinates voluntary movement. Important for balance and coordination. Also called the little brain. Without the cerebellum, you can still move but you won’t have good balance or coordination.
Executive Functions
The cognitive processes that allow us to plan, focus attention, and organize multiple tasks to complete our goal. Associated with the function of the prefrontal cortex.
Corpus Callosum
The bridge of fibers that connects the two halves of the brain (the section of the brain that connects the left and right hemispheres). All communication about tasks must pass through this area.
Contralateral Control
The opposite-side organization of the brain, whereby one side of the body is connected to and controlled by the opposite brain hemisphere. The hemisphere controls the opposite side of the body and senses go to the opposite hemisphere.
Split-Brain Procedure
The severing of the corpus callosum to reduce the spread of seizures across brain hemispheres.
Dendrite
The part of the neuron that receives chemical messages from other neurons.
Cell Body/Soma
The part of the neuron that collects neural impulses, contains the nucleus, and provides life-sustaining functions for the cell.
Axon
The part of the neuron that transports electrical impulses to other neurons via the terminal branches.
Terminal Branches/Buttons
The part of the neuron that converts electrical signals into chemical messages to other neurons.
Myelin Sheath
A layer of fatty tissue that covers and insulates an axon to ensure that electrical messages travel fast and meet less resistance. Wrapped around the neuron’s axon. Supplied by surrounding glia cells.
Glial Cells/Glia
The cells that make up the myelin sheath around neurons to insulate, support, and nourish neurons and modulate neuronal function.
Action Potential
A rapid change in voltage created by a neuron when it is sufficiently stimulated to surpass a critical threshold. Serves as the basis for neural signaling. A shift in electrical charge, starting at the base of the axon and travelling down its length. Are all-or-none.
Ion Channels
The channels that allow chemical ions to enter and exit the neuronal membrane to generate the voltage for the resting and action potentials.
Depolarization
Occurs when a neuron’s voltage becomes more positive. The first phase of the action potential.
Voltage Threshold
The voltage necessary for a neuron to start an action potential.
Repolarization
The portion of the action potential during which the neuron returns to its resting potential.
Refractory Period
The period of time required for a neuron to return to its resting state before it can fire another action potential.
Excitatory Messages
Moves the voltage of the neuron closer to its threshold. Sodium channels open (sodium enters and charge becomes more positive).
Inhibitory Messages
Moves the voltage of the neuron farther away from its threshold. Potassium channels open (potassium exits and charge becomes more negative).
Synapse
The gap where a sending neuron communicates with the dendrites or cell body of the receiving neuron (gaps between neurons).
Neurotransmitters
The chemical messengers released at the terminal branch to allow communication between neurons. Chemical messengers released after an action potential that travels across the synapses. Are uniquely shaped and can only bind to certain receiving dendrites.
Amino Acids
The brain’s most abundant class of neurotransmitters including glutamate (important for neuronal excitation) and gamma-aminobutyric (GABA, important for neuronal inhibition and the regulation of muscle tone).
Monoamines
A neurochemical class that includes norepinephrine, dopamine, and serotonin. Important for fight-or-flight and reward responses.
Acetylcholine (ACh)
A major neurotransmitter class that can behave as both an inhibitory and excitatory signal, supporting heart and skeletal muscle, and cognitive function. Found at the neuromuscular junction (the synapse between a motor neuron and a muscle fiber). Controls movement. Role in attention and memory (cognitive functioning).
Agonist
A chemical that mimics or increases the action/effect of a neurotransmitter. Ex. Black Widow Spider venom increases release of ACh which results in violent muscle contractions that lead to paralysis due to loss of ACh supply. Ex. prozac blocks the reuptake of serotonin leaving more in the synapse (relieves depression symptoms).
Antagonist
A chemical that competes with a naturally occurring neurotransmitter to block or inhibit the effects of neurotransmission. Ex. botulin blocks release of ACh which causes paralysis. Ex. curare blocks the ACh receptor site which causes paralysis.
Parts of a Neuron
1) Cell Body/Soma
2) Dendrites (receive information “listeners”)
3) Axon (sends the message to adjacent cells “speakers”)
4) Axon Terminals/Terminal Buttons (release neurotransmitters)
(Electro)chemical
A shift in electrical charge that travels along the axon.
Electro(chemical)
The release of neurotransmitters that travel from one neuron to the next.
Resting Potential
The inside of a neuron is more negatively charged than the outside (polarized) (-70 mV).
Neural Communication
1) At rest, the inside of the cell is more negative than the outside. When possible, positive ions want to rush in.
2) Stimulation from dendrites affects the electrical charge. When it reaches the voltage threshold or threshold of excitation (-55 mV) an action potential occurs.
3) When an action potential begins, sodium channels open and positively charged sodium enters the cell.
4) Sodium channels close and potassium channels open. Potassium exits bringing charge back to resting potential.
5) Eventually the potassium channels close as well but by that time too many positively charged ions have left the cell. Cell must now reset to prepare for the next action potential.
Nodes of Ranvier
Unmyelinated sections of the axon that allow action potentials to occur.
Saltatory Conduction
The signal “jumps” from one node to the next allowing for faster transmission.
Multiple Sclerosis (MS)
When the immune system turns on the body causing the hardening of the myelin insulation. Symptoms are optic neuritis (painful vision loss), reduced balance and fine motor control, constant state of tiredness, and numbness or tingling in the extremities. There is no cure for this disease. Focus is on treatment of symptoms and modifying the course of the disease (ex. interferons). Genetic and environmental factors contribute to this. Women are 3 times as likely as men to develop MS. Identical twins have 33% chance of developing MS (if one twin has MS, the other is more likely to get it). Positive correlation between risk and distance from equator (the further you live from the equator, the higher your risk of getting MS).
Optic Neuritis
Painful vision loss.
Synaptic Transmission
1) Action potential reaches axon terminal.
2) Calcium channels open.
3) Calcium ions cause vesicles to release neurotransmitters.
4) Neurotransmitters cross the synapse.
5) Neurotransmitters bind to neuroreceptors.
6) Trigger signal in post-synaptic neuron.
Glutamate
Excitatory effect. Linked to forming memories. Excessive glutamate can trigger seizures.
GABA
Inhibitory effect. Influences muscle tone, facilitates sleep, and reduces arousal. Epilepsy meds increase the action of GABA.
Serotonin (5-HT)
Affects mood, hunger, sleep, and etc. Serotonin levels may be linked to depression (ex. prozac, an antidepressant, raises serotonin by blocking the reuptake).
Dopamine (DA)
Involved in reward and pleasure, learning, and movement. There are abnormal levels of dopamine levels in schizophrenia (high levels), ADHD (low levels), and Parkinson’s (low levels).
Drug
An outside (exogenous) substance not necessary for normal function which alters the function of cells (cause changes in physiology and behaviour ex. ritalin blocks reuptake of dopamine which increases attention). Affect brain chemistry at synapses.
Psychoactive Drug
A chemical substance that alters perceptions and mood (ritalin is psychoactive, Tylenol is not).
Franz Gall (1800s)
Came up with the idea that different areas of the brain were connected to bumps on the skull that revealed mental abilities and traits (ex. loving your children). Is wrong but it is right that the brain has regions with certain functions.
Main Parts of the Brain
1) Hindbrain (oldest evolutionary part of the brain (reptilian))
—> Medulla
—> Pons
—> Cerebellum
2) Midbrain
3) Forebrain (newest evolutionary part of the brain (mammalian))
—> Basal Ganglia
—> Amygdala
—> Hippocampus
—> Hypothalamus
—> Thalamus
—> Cerebral Cortex
——> Frontal Lobe
——> Parietal Lobe
——> Occipital Lobe
——> Temporal Lobe
Phineas Gage
A railroad foreman in 1848. A large rod went through his head and destroyed his frontal lobe. He survived with an altered personality.
Aphasia
Language impairment due to damage to the left temporal lobe. Result is an inability to speak (Broca’s) and/or understand what others say (not speaking properly, words come out jumbled even though they think they are speaking properly) (Wernicke’s).
Spatial Neglect
Attention impairment due to damage to the right parietal lobe, result is a failure to attend to objects in left space. Doesn’t occur vice versa.
Left Hemisphere
Controls language.
Right Hemisphere
Controls spatial ability.
Temporal Lobe Left
Controls grammar, vocabulary, literal meaning, and speech.
Temporal Lobe Right
Controls emotional content of words and metaphors.
Parietal Lobe Left
Controls reading, writing, and math (involve spatial functions).
Parietal Lobe Right
Controls spatial awareness.
If An Image Is Flashed to the Right Visual Field
The patient can name the object (left = language).
If An Image Is Flashed to the Left Visual Field
The patient reports seeing nothing but they can point to the correct object with their right hand.
Hydrocephalus
Cerebrospinal fluid builds up and destroys cell bodies of neurons as well as connections between neurons (white matter).
Neural Plasticity
The capacity of the brain to modify itself, functionally and structurally, in response to experience and injury.
