Neuroscience Flashcards
1
Q
Sensory Neurons
A
Receive information from external world and relays them to the brain via spinal cord
2
Q
Motor Neurons
A
Carries signals from the spinal cord to the muscles to produce movement
3
Q
Interneurons
A
Connects sensory, motor, and/or other interneurons
4
Q
Does location matter for nerve cell specialization?
A
Yep
5
Q
True or False: We use only 10% of our brains
A
False.
Why would we only use 10% of our brains? That’s a lot of space and a lot of blood wasted
6
Q
Central Nervous System (CNS)
A
-Brain
-Spinal Cord
-Optic Nerve
-Retina
7
Q
Peripheral Nervous System
A
Cranial Nerves
8
Q
Neurons
A
The cell that receives and sends signals
-Depends on oxygen and glucose being constantly delivered to them
-Cell body, dendrite, axon
9
Q
Glial Cells
A
Provide structural, nutritional, and other types of support to the brain
10
Q
Dendrites
A
Tapered extensions of the cell body
Receive information from other neurons and pass them to the soma
11
Q
Axon
A
Single cylindrical; may be many centimetres long; may be myelinated or unmyelinated
Conduct info to other neurons
12
Q
Axon terminals
A
Transmit information to other neurons
13
Q
Synaptic terminal
A
Spherical sac containing neurotransmitters
14
Q
Neurotransmitter
A
Chemical messengers that move between neurons
15
Q
Synapse
A
-Synaptic cleft is the actual gap
-An intracellular site where fast, highly localized transmission of chemical and electrical signals occur
16
Q
Can any receptor pick up any signal?
A
NO
Receptors are specific to specific neurotransmitters
17
Q
Unipolar Neuron
A
Single process extending from the cell body
-Common in invertebrates
18
Q
Bipolar Neuron
A
Two processes extending from the cell body
-Often sensory neurons
19
Q
Multipolar Neuron
A
Multiple processes extending front the cell body
-Most common in vertebrates
20
Q
What is the charge and chemical gradient of a neuron
A
“The Salty Banana”
Lots of potassium (K) inside the neuron
(-) charge in neuron
Lots of sodium (Na) outside the neuron
(+) charge outside the neuron
21
Q
Resting potential
A
~ -60-70 mV Difference in electrical charge across the neurological membrane
-When the neuron is not being stimulated or inhibited
22
Q
Depolarization
A
-The reduction of a membrane’s resting potential so it becomes less negative
-Starts a chain reaction
-Leads to action potential
23
Q
Refractory Period
A
When the neuron cannot fire = Absolute refractory period
Relative refractory period (action potential ma happen, but it needs to be a lot)
24
Q
How do neutrons increase the intensity of a response
A
In order to increase intensity of response, neurons shoot more frequently
25
What do myelin sheaths do?
They make nerve impulses faster
26
Do neurotransmitters only trigger neurons?
No. Neurotransmitters can also tell neurons not to fire
27
Postsynaptic potential (PSP)
A voltage at a receptor site on a postsynaptic cell membrane
28
Excitatory PSP
A positive voltage shift that increases the likelihood that the postsynaptic neuron will fire action potentials
-Caused by excitatory neurotransmitters
29
Inhibitory PSP
-Makes membrane potential more negative
-Makes it harder to cause an action potential
30
Reuptake
Reabsorption of neurotransmitters from the synaptic cleft by the presynaptic membrane
31
Does a single neuron create a response?
ONE NEURON IS KINDA USELESS
You need millions to send signals
32
List four neuropeptides
-Endorphins
-Pituitary peptides
-Hypothalamic peptides
-Brain-gut peptides
-Opioid peptides
-Miscellaneous peptides
33
Acetylcholine (ACh)
First transmitter discovered
-Plays a large role in voluntary muscle movement
-Contributes to the regulation of attention, arousal, and memory
-Plays a role in sleep
-Often found in poisons (black widow spider venom have this)
-Causes massive release of ACh (leads to muscle pain, tremors, nausea)
-Botox causes paralysis by blocking ACh at synapses
-Alzhiemers is associated with low levels of ACh
-Nicotine behaves like ACh by binding to its receptors
34
Agonist
A chemical that mimics the action of a neurotransmitter
35
Antagonist
A chemical that fight the neurotransmitter
36
Dopamine (DA)
Contributes to voluntary muscle movements
-The reward pathway?
-Degeneration of DA is associated with Parkinson's disease
-Over action of dopamine is associated with schizophrenia
37
Serotonin (5-HT)
-Involved in regulation of sleep and wakefulness, eating, and aggression
-Prozac and similar antidepressant drugs affect serotonin circuits
-Serotonin is not the solution to all mental issues, causes are multifactorial
-5-HT refers to the chemical name
38
Norepinephrine (NE)
Both a neurotransmitter and hormone
-Associated with brain arousal, mood, hunger, sleep, and sexual behaviour
-Generates fight or flight response
-Increases heart rate, blood pressure, increased blood flow
-Drugs like meth and other amphetamines more
39
GABA
Gamma-aminobutyric acid
-Only has inhibitory effects
-Contributes to regulation of anxiety and sleep/arousal
40
Glutamate
Main excitatory neurotransmitter in the nervous system: participates in relay of sensory information and learning
41
Anandamide
Binds to the same neurotransmitters as THC, the active ingredient in cannabis leaves (devils lettuce)
-Comes from the sanskrit word “ananda” which means joy
-Likely plays a role in eating, memory, motivation and sleep
-Occurs in both the central and peripheral nervous system
-Pain, fear, and healing?
42
Endorphins
Neuropeptide
-Naturally occurring analgesic (painkiller)
-Both a hormone and neurotransmitter
-Mostly regulated by the peripheral nervous system
-Insensitivity to pain (oversupply)
-Hypersensitivity to pain (undersupply)
-Subtle euphoric effect
Exercise gives you endorphins, and endorphins make you happy, and happy people don’t kill their husbands
43
Endocrine System
Series of glands the produce chemical substances known as hormones
-Slow chemical messengers that travel through the bloodstream
-Effect linger longer, and effect more of the body
Pituitary gland is the master gland - It regulates many other hormone glands
44
Neural Plasticity - Neuroplasticity
Your brain can change and adapt
45
Early Development Neuroplasisity
1. Growth of dendrites and axons
-We need those
2. Synaptogenesis
-Formation of new synapses
3. Pruning
-Removal of extra synapses to increase the efficiency of a neural network
-Occurs until about 10
-Approx. 70% of neurons die off
4. Myelination
-Insulation of axons with myelin sheath
46
Neural Plasticity and learning
Long-Term Potentiation of synapses
-A long lasting enhancement in signal transmission between two neurons that results from stimulation the synchronously
-Increasing the efficiency of neurons; making it more likely that neurons will fire
-Neurons that fire together, wire together
Structural changes
-Axonal growth
-Dendritic growth
47
Neural Plasticity following Injury
Brain regions sometimes take over function previously performed by others
-Neurons don't regrow or regenerate in the brain, but other regions can sometimes compensate
48
What are the potential uses of stem cells in treating brain damage and disorders
Stem Cells
-Potential to offer treatment for Alzhiemers, stroke, Parkinson’s, Diabetes, Bindless, Deafness, Infertility, and numerous other thing
49
Neurogenesis
Creation of new neurons in the brain
-Certain areas of the brain allow creation of new neurons (not common)
50
Maninges
Three protective membrane that cover the brain and spinal cord
-Dura mater
-Arachnoid mater
-Pia mater
51
Cerebral Ventricles
Small pockets that contain cerebrospinal fluid, that cushion the brain
52
Franz Joseph Gall (1758-1828)
-All mental functions arise from the brain
-Mind and the body are not separate entities
-Brain consists of functional regions
-Also a proponent of phrenology (not very good)
-Brain has distinct functional regions
53
Cerebral Cortex
Outermost part of forebrain, responsible for analyzing sensory processing and “higher” brain functions
Cerebral hemispheres
-The two halves of the cerebral cortex
54
Frontal Lobe and its parts
Consciousness
Primary motor cortex
-Responsible for body movement
Prefrontal cortex (frontiest part)
-Thinking, planning, language
Broca’s Area
-Language area in the prefrontal cortex that helps to control speech production and some aspects of speech comprehension
55
Phineas Gage
Got impaled straight through the skull, and survived
Major personality changes (became more antisocial)
56
Parietal lobe
Processes touch information, integrates vision and touch
Primary Somatosensory Cortex
-Regions of the cerebral cortex that initially process information form the senses
-Soma = Body Sensory = Feeling
57
Temporal Lobe
Processes auditory information language and autobiographical memory
-Identified by the lateral Fissure/Sulcus
Wernicke’s Area
-Part of the temporal lobe involved in understanding speech
-Damage to it makes speech hard to understand (also makes people spew word salads)
58
Occipital Lobe
Specialised for vision
59
The Basal Ganglia
A group of nuclei located beneath the cerebral cortex
-Involved in goal-directed motor control
-Contains dopamine neurons and is closely associated with reward and motivation
60
The Limbic System
A loosely connected network or structures located roughly along the border between the cerebral cortex and deeper subcortical areas
-Plays a role in olfaction, motivation, memory
61
Thalamus
Gateway from sense organs to the primary sensory cortex
-All sensory information (except smell) is relayed through the thalamus
Think mailroom in an office building
62
Hypothalamus
The part of the brain that regulates the pituitary gland and is responsible for maintaining a constant internal state
-The four "f"s (fleeing/fighting/feeding/sexual behaviour (fortification))
-Body temp
-Hunger/thirst
-Sleep
-Emotional regulation
63
Hippocampus
Part of the brain that plays a role in spatial memory and may be necessary for the formation of new memories
-Damage to this region often makes it difficult to form new memories
64
Clive Wearing
Had retrograde amnesia and anterograde amnesia
-Often confused and angry
-Was a conductor and musician
Able to play music because it relied in procedural memory
65
Amygdala
Part of limbic system that plays a key role in fear, excitement, and arousal
-Makes you view facial expressions as emotional stimuli
-A contributor in fear conditioning
66
Brain Stem
Consists of the midbrain, pons, and medulla
67
Midbrain
Part of your brain that contributes to movement, tracking of visual stimuli, and reflexes triggered by sound
-Plays a role in hostage situations? Snipers are trained to shoot this
68
Pons
Connects the brainstem to the cerebellum
69
Medulla
Part of the brainstem that regulates breathing and heart rate
70
Cerebellum
Hindbrain structure
-Responsible for smoothie and finessing fine motor control initiated by other brain regions
Likely plays a role in;
-Executive function
-Spatial abilities
-Aspects of language
71
Spinal Cord
The main way your body communicates with your brain
Sensory nerves send info to brain
Motor nerves send info to body
Interneurons are the intermediary
Interneurons connect sensory and motor nerves so info doesn’t need to go to the brain
Reflex Arc
72
What are the two branches of the peripheral nervous system (PNS)
Somatic Nervous system
Autonomic nervous system
-Sympathetic
-parasympathetic
73
Sympathetic nervous system
Active during high stress states
-Gets you ready for action (fight or flight)
-Increase in heart rate
-Increases in respiration and perspiration
74
Parasympathetic nervous system
The system that activates during rest and digestion
-Sexual Arousal
-Digestion
-Urination
75
Phenology
Was never accepted mainstream medical opinion
-The domain of immature doctors
-Popular in the victorian area
-Claims were anecdotal
Assumed they could measure the brain by looking at the bumps on a person’s head
“Getting your head checked out”
Note- your brain has the consistency of jello, it won't change your skull shape
76
Stereotaxic Methods
Ex. mapping a rat’s brain to lesion parts of the brain, then induce damage with precision, stitch head back up and examine behavioiur
Brain surgery is always performed while the subject is awake and alert
-Only local anaesthesia
-Advantageous for surgeons because the doctor can see if what they do is causing damage
Localized brain functions can be assessed by examining brain damage and seeing what behavioural issues arise from it
-Neuropsychological testing
77
Electroencephalograph
Records the brain’s electrical activity at the surface of the skull
Pros
-Used in human and nonhuman animals
-Detects rapid changes in electrical activity
-Non-invasive
Cons
-Low spatial resolution (you can’t pinpoint the electrical activity with high levels of precision)
78
Non-Functional Brain Scans
CAT scan
MRIs
79
Computed Tomography (CT) - “CAT scan”
Uses multiple X-rays to construct three-dimensional images
80
Magnetic Resonance Imaging (MRI)
-Uses strong magnetic fields to indirectly visualize brain structure
-Better suited than CAT scans to image soft tissue
81
Functional Brain Scans
Positron Emission Tomography (PET)
Functional MRI (fMRI)
82
Positron Emission Tomography (PET)
Invasive imaging technique that measures consumption of glucose-like molecules, yielding a picture of neurological activity
CONS:
People don’t like needles
They don’t like needles with radioactive materials
83
Functional MRI (fMRI)
Uses magnetic fields to visualize brain activity using the BOLD response
-BOLD = Blood oxygen level dependent (active brain cells need more blood)
-Highly sensitive to motion
-Questions about data analysis (subtraction method makes it hard to really tell what the info means? is a signal excitatory or inhibitory?)
84
Transcranial Magnetic Stimulation (TMS)
Enhances or interrupts brain function
-Noninvasive
85
What is the problem in measuring neurons
Main problem in viewing brains is that neurons are so densely packed
86
Golgi Stain
A neural stain that completely darkens a few of the neurons in each slice of tissue, thereby revealing their silhouettes
-Doesn't colour all neurons
87
Nissl Stain
Has an affinity for structure in neuron cell bodies
88
Electron Microscopy
A microscopy technique used to study the fine details of cellular structures
