Brain Biology Flashcards
1
Q
Sensory Neurons
A
- afferent neurons
- sensory information -> spinal cord -> brain
2
Q
Motor Neurons
A
- efferent neurons
- motor information from brain/ spinal cord -> muscles/glands
3
Q
Interneurons
A
- most numerous type of neuron
- located mostly in the brain and spinal cord
4
Q
Reflex Arcs
A
- neural circuits
- link interneurons to reflexive behavior
5
Q
CNS
A
brain and spinal cord
6
Q
PNS
A
- peripheral nervous system
- includes somatic ns and autonomic ns (parasympathetic and sympathetic)
7
Q
Somatic Nervous System
A
- sensory and motor neurons in skin, joints, muscles
- sensory to afferent fibers and motor to efferent fibers
8
Q
Autonomic Nervous System
A
- regulates heartbeat, respiration, digestion, glandular secretions
- involuntary
- responsible for homeostasis
- related to emotion because specific physiological reactions are associated with specific emotions
9
Q
Parasympathetic Nervous System
A
- conserves energy
- ‘rest and digest’
- Ach is the main NT
- constricts pupils, stimulates saliva, constricts bronchi, slows heartbeat, stimulates peristalsis and secretion, stimulates bile release, contracts bladder
10
Q
Sympathetic Nervous System
A
- activated by stress
- ‘fight or flight’
- Epi is main NT
- increases heart rate, sends blood to muscles, increases blood glucose concentration (via cortisol stimulation of gluconeogenesis), relaxes bronchi, decreases digestion, dilates eyes
11
Q
Meninges
A
- thick sheath of connective tissue covering the brain
- helps protect brain
- anchors brain in skull
- resorbs cerebrospinal fluid
- composed of 3 layers: dura mater (right under bone), arachnoid mater (middle), pia mater (closest to brain)
12
Q
What are the subdivisions of the forebrain?
A
- cerebral cortex
- basal ganglia
- limbic system
- thalamus
- hypothalamus
13
Q
What are the subdivisions of the midbrain?
A
- inferior colliculus
- superior colliculus
14
Q
What are the subdivisions of the hindbrain?
A
- cerebellum
- medulla oblongata
- reticular formation
15
Q
Functions of Hindbrain (Rhombencephalon)
A
-controls balance, motor coordination, breathing, digestion, arousal
16
Q
Functions of Medulla Oblongata
A
- part of hindbrain
- regulates vital functions like heart rate, BP, breathing, digestion
17
Q
Functions of Cerebellum
A
- part of hindbrain
- refined motor movements
- maintains posture, balance, coordinates body movements
- alcohol impairs this area
18
Q
Functions of Reticular Formation
A
- part of hindbrain
- arousal and alertness
19
Q
What is the Pons?
A
- part of hindbrain
- contains sensory and motor pathways between cortex and medulla
20
Q
What happens if there is damage to the Cerebellum?
A
- clumsiness
- slurred speech
- loss of balance
21
Q
Functions of Midbrain (Mesencephalon)
A
- receives sensory and motor information from body
- associated with involuntary reflex responses triggered by visual or auditory stimuli
22
Q
Functions of Superior Colliculus
A
- part of midbrain
- sensorimotor reflexes
- nuclei here receive visual input
23
Q
Functions of Inferior Colliculus
A
- part of midbrain
- sensorimotor reflexes
- nuclei here receive sensory information from auditory input
24
Q
Functions of Forebrain (Prosencephalon)
A
- associated with complex perceptual, cognitive, and behavioral processes
- associated with emotion and memory
- has greatest influence on behavior
- most ‘modern’ and largest portion of brain by weight and volume
25
During embryonic development what does the prosencephalon divide into?
- telencephalon (cerebral cortex, basal ganglia, limbic system)
- diencephalon (thalamus, hypothalamus, posterior pituitary gland, pineal gland)
26
During embryonic development what does the rhombencephalon divide into?
- myelencephalon (medulla oblongata)
| - metencephalon (pons, cerebellum)
27
Functions of Thalamus
- part of forebrain
- relay station for sensory all information besides smell
- sorts and transmits information to appropriate areas of cerebral cortex
28
Functions of Hypothalamus
- part of forebrain
- 4Fs: feeding, fighting, flighting, (sexual) functioning
- serves homeostatic functions
- key player in emotional experience
- part of endocrine response
- receptors here regulate metabolic, temperature, and water balance
- synthesizes and releases NTs
29
Lateral Hypothalamus
- part of forebrain
- hunger center because has receptors to detect when body needs more food/fluids
- when destroyed one Lacks Hunger
30
Ventromedial Hypothalamus
- part of forebrain
- satiety center
- signals to stop eating
- when destroyed one is Very Much Hungry
31
Anterior Hypothalamus
- part of forebrain
- controls sexual behavior
- regulates sleep and body temperature
- when destroyed one is Asexual
32
Posterior Pituitary
- part of forebrain
- axonal projection of hypothalamus
- releases ADH (vasopressin) and oxytocin
33
Pineal Gland
- part of forebrain
- secretes melatonin which regulates circadian rhythms
- receives signals from retina for coordination with sunlight
34
Functions of Basal Ganglion
- part of forebrain
- coordinates muscle movement
- receives information from cortex and relays information to the spinal cord
- functions as a extrapyramidal system -- gathers information about boy position and carries information to CNS but not directly via motor neurons
35
Describe Parkinsons Disease
- results from destruction of portions of basal ganglia
| - loss of dopaminergic neurons in basal ganglia
36
Functions of Limbic System
- part of forebrain
- consists of interconnected structures in central brain
- associated with emotion, memory, and motivation
- includes amygdala, thalamus, hypothalamus, hippocampus, fornix, septal nuclei, parts of cerebral cortex
37
Functions of Amygdala
- part of limbic system
- signals cortex about stimuli related to attention and emotions
- processes the environment, detects external cues, and learns from surroundings to produce emotion
- associated with fear and interpretation of facial expressions
- controls implicit memory system
38
Functions of Hippocampus
- part of limbic system
- located in temporal lobe
- involved in creating long term memories
- aids in creating context for stimuli to lead to an emotional experience
- primarily controls explicit memory
39
Functions of Septal Nuclei
- part of limbic system
| - contain a primary pleasure center associated with addiction
40
What is a Fornix?
long projection from the hippocampus that allows for communication with parts of the limbic system
41
Describe Anterograde Amnesia
- occurs when one can't establish new long term memories
| - what HM had when parts of his amygdala and hippocampus was removed
42
Describe Retrograde Amnesia
- occurs when there is damage to the hippocampus
| - occurs when there is memory loss of events that occurred before a brain injury
43
Functions of Cerebral Cortex
- part of forebrain
- outer surface of the brain, sometimes called neocortex
- complex perceptual, cognitive, and behavioral processes
- divided into 4 lobes: frontal, parietal, occipital, temporal
44
Frontal Lobe
- comprised of the prefrontal cortex and motor cortex
| - Broca's Area is located here
45
Prefrontal Cortex
- manages executive functions
- supervises processes associated with perception, memory, emotion, impulse control, decision making, expressing personality, and long-term planning
- example of association area -- integrates input from diverse brain regions
- receives arousal input from brainstem
46
What happens if there is damage to the Prefrontal Cortex?
- vulgar/sexually inappropriate comments
- apathetic
- impulsive
- depressed
47
What side of the PFC is associated with positive emotions?
Left PFC
48
What side of the PFC is associated with negative emotions?
Right PFC
49
What is the Dorsal Prefrontal Cortex associated with?
associated with attention and cognition
50
Role of Ventral Prefrontal Cortex
connects with regions of brain responsible for experiencing emotion
51
Role of Ventromedial Prefrontal Cortex
- decision making
| - controls emotional responses from amydgala
52
Primary Motor Cortex
- initiates voluntary movements
| - has a motor homunculus
53
Broca's Area
- found in left hemisphere
| - involved in speech production
54
What lobes does the central sulcus divide?
frontal lobe and parietal lobe
55
What are gyri?
-bumps on the cerebral cortex of the brain
56
What are sulci?
* Silicon Valley*
| - folds on the cerebral cortex of the brain
57
Parietal Lobe
- processes sensory information that has to do with taste, temperature, pressure, pain, and touch
- somatosensory cortex is located here and it is a projection that receives sensory signals
- central region is associated with spatial processing and manipulation
58
Occipital Lobe
- contains the visual cortex which is striated (striped)
| - some areas are involved in learning and motor control
59
Temporal Lobe
- contains auditory cortex (sound processing)
- contains Wernicke's Area (associated with language reception and comprehension)
- functions in memory processing, emotion and language
60
What does it mean when we say the brain works contralaterally?
one side of brain communicates with opposite side of body
61
What brain hemisphere functions in ipsilaterally?
the cerebral hemisphere communicates with the same side of the body (ex. hearing)
62
Functions of Left Hemisphere
- typically the dominant hemisphere
| - associated with analytic functions, language, logic, math skills, movement
63
Functions of Right Hemisphere
- typically the nondominant hemisphere
- associated with intuition, creativity, music cognition, spatial processing
- interprets language according to emotional tone
64
Acetylcholine
- found in the CNS and PNS
- works on nicotinic and muscarinic receptors
- agonists: nicotine, muscarine, cholinesterase inhibitors
65
Role of Ach in the CNS
-attention and arousal
66
Role of Ach in the PNS
- transmits nerve impulses to muscles at NMJ
| - use mostly by the parasympathetic ns
67
Epinephrine
- catecholamine
- active sympathomimetic hormone from the ADRENAL MEDULLA
- stimulates both the alpha- and beta- adrenergic systems, causes systemic VASOCONSTRICTION and gastrointestinal relaxation, stimulates the HEART, and dilates BRONCHI and cerebral vessels
- adrenaline
- plays a big role in 'fight or flight' response of sympathetic NS
68
Dopamine
- catecholamine
- derived from TYROSINE
- precursor to NOREPINEPHRINE and EPINEPHRINE
- major transmitter in the extrapyramidal system of the brain, and important in regulating movement
- binds to alpha-1 and beta-1 adrenergic receptors
- imbalances in transmissions of this play a role in schizophrenia
- increased concentration of this in the basal ganglia
69
Norepinephrine
- catecholamine
- precursor of epinephrine
- secreted by the ADRENAL MEDULLA
- widespread central and autonomic NT (sympathetic ns)
- principal transmitter of most postganglionic sympathetic fibers
- directly stimulates adrenergic receptors
- involved in controlling alertness and wakefulness
- decreased levels lead to depression
- increase levels lead to mania/anxiety
70
Serotonin
- classified as a monoamine
- biochemical messenger and regulator
- synthesized from the essential amino acid L-Tryptophan
- acts as a local transmitter at synapses, and as a paracrine or hormonal modulator of circuits upon diffusion, allowing a wide variety of "state-dependent" behavioral responses to different stimuli
- modulates sleep, the arousal state, sexual behavior, mood, eating and dreaming
- deficiencies cause disorders such as depression, obsessive-compulsive disorder, phobias, posttraumatic stress disorder, epilepsy, anxiety disorder
71
GABA
- produces IPSPs
- stabilizes neural activity in brain
- causes hyperpolarization of postsynaptic membrane in CNS
- inhibitory NT
72
Glycine
- inhibitory NT in CNS b/c it increases Cl- influx into neuron via binding to ionotropic receptors
- non-essential, non-polar, non-optical, glucogenic amino acid
73
Glutamate
- excitatory NT in CNS
- key molecule in cellular metabolism
- most abundant fast excitatory neurotransmitter in ns
- acts on receptors like NMDA
- involved in cognitive functions like learning and memory
74
List the methods used to map the brain
- EEG
- rCBF
- CT
- PET
- MRI
- fMRI
75
Electroencephalogram (EEG)
- electrical activity generated by larger groups of neurons
- place electrodes on scalp
- noninvasive
- relatively cheap
- low resolution
76
Regional Cerebral Blood Flow (rCBF)
- detects broad patterns of electrical activity
- based on increased blood flow to active parts of brain
- noninvasive
77
CT
- multiple x-rays taken and processed into cross-sectional slices of tissue
- reasonably cheap
- often done on patients who can't stay in a MRI machine
- can be done quickly (ex. stroke pts)
78
PET
- radioactive isotope agent injected into body -> annihilation event (isotope meets electrons in body) -> photons released
- imaging shows agent's dispersion and uptake throughout target tissues
- measures photons
79
MRI
- magnetic field interactions with hydrogen
- maps hydrogen dense regions of body
- takes hours to do
- very expensive
- high resolution -- golden standard
- no radiation
80
fMRI
- measures changes associated with blood flow
- way of monitoring neural activity
- increased blood flow (oxyhemoglobin) = increased activation
- measures where oxygenated vs deoxygenated blood is
81
Endorphins
- natural painkiller
- produced in CNS and pituitary gland
- actions similar to morphine and other opiods
82
Which two imagining techniques are used to show brain structural information?
- MRI
| - CT
83
Which 3 imagining techniques are used to show brain function?
- fMRI
- PET
- EEG
84
Does a MRI or CT scan provide a higher resolution image of the brain?
MRI
85
Does a MRI use radiation?
No
86
Phineas Gage
- railroad accident lead to lesion of his frontal lobe
- resulted in drastically different personality
- unable to do randomized control trials because unethical, but can be done in animals
87
Knock-Out Models
- specific gene is taken out from an organism/animal
- genes can be for receptors for NTs, etc
- can see how this impacts animals growth function
88
Knock-In Models
- specific gene is added to an organism/animal that usually does not have this gene
- can see how this impacts animals growth function
89
In ______ there is stimulation of different electrical pathways and can see the effects.
Electrophysiology
90
Deep Brain Stimulation is often used in treatment of ___ Disease, and helps create ___ of neurons.
- Parkinsons
| - firing
