1What did the human brain evolve from?
A neural tube
2What organism resembles early vertebrate brains?
Lancelet Amphioxus
3What did early simple brains process?
Light, chemicals
4What three bulges form the brain?
Forebrain, midbrain, hindbrain
5What expanded to detect chemicals?
Olfactory bulbs
6Why did visual regions expand?
Image-producing eyes
7What controls escape and orientation?
Cerebellum
8Why are escape movements important?
Active swimming
9What formed the cerebral hemispheres?
Expanded forebrain
10What expanded in early mammals?
Cortex, cerebellum
11How does brain info travel?
Neural chains
12What are nerve tracts?
Neuron bundles
13What connects brain hemispheres?
Corpus callosum
14What connects temporal lobes?
Anterior commissure
15What is a neural network?
Linked nerve tracts
16What do neural networks do?
Route signals
17Where does movie processing start?
Photoreceptors
18Where do visual signals go next?
Optic tract
19What does the thalamus do?
Processes, relays signals
20Where is the visual cortex?
Occipital lobe
21What does it do?
Edges, 3D vision
22What does the temporal lobe do?
Identify objects
23What does the parietal lobe do?
Locate objects
24What is a thalamocortical loop?
Thalamus–cortex circuit
25What does the loop produce?
Brain waves
26How are brain waves measured?
EEG
27When do alpha waves occur?
Relaxed, eyes closed
28Where do alpha waves start?
Parietal, occipital lobes
29Alpha wave frequency?
8–13 Hz
30When do beta waves occur?
Task focus
31Beta wave origin?
Frontal, parietal lobes
32Beta wave frequency?
14–30 Hz
33When do theta waves occur?
Light sleep
34Theta wave frequency?
4–7 Hz
35When do delta waves occur?
Deep sleep
36Delta wave frequency?
<3.5 Hz
37Which waves are strongest?
Alpha, delta
38What are spinal tracts?
Neuron chains
39Spinal signal directions?
Up, down
40What do basal ganglia do?
Movement feedback
41What do cerebellum loops do?
Timing, strength
42What adds emotional context to movement?
Cortex tracts
43What does hippocampus check?
Signal familiarity
44What do memory loops affect?
Behavior, response
45What are reflex loops?
Automatic circuits
46Where are reflexes controlled?
Spinal cord
47What are neural circuits?
Local neuron chains
48What do circuits produce?
Output patterns
49Where are circuits dense?
Cortex
50How are neurons arranged?
Layers, columns
51How do signals flow?
Neuron to neuron
52What is a column’s role?
Specific task
53What affects column output?
Nearby circuits
54What is each neuron like?
Microprocessor
55Why is this useful?
Flexibility
56What are the two types of neurons?
Excitatory, inhibitory
57What percent of neurons are excitatory?
80 percent
58What is the most common excitatory neuron?
Pyramidal cell
59What shape is a pyramidal cell?
Cone-shaped
60Where are pyramidal dendrites located?
Apex, base
61What do pyramidal dendrites collect?
Incoming signals
62What does a pyramidal axon do?
Sends one signal
63What percent of neurons are inhibitory?
20 percent
64What do inhibitory neurons do?
Suppress neighbors
65Which type sends outputs?
Excitatory neurons
66Which type loops back?
Inhibitory neurons
67What helps tune signals?
Signal interplay
68What disorder can result from imbalance?
Epilepsy
69What do feed-forward inhibitory circuits do?
Inhibit neighbors
70What is feedback inhibition?
Inhibits upstream layers
71What do recurrent networks involve?
Feedback loops
72What is the functional unit of neural circuits?
Neuron
73What are the parts of a neuron?
Soma, dendrites, axon
74What is another name for cell body?
Soma
75What do dendrites collect?
Incoming signals
76What carries signals away?
Axon
77What ends an axon?
Axon terminals
78Where are signals passed?
Synapse
79How long can axons be?
Over one meter
80What are neuron support cells?
Glia
81Old glia-to-neuron ratio?
10:1
82New glia-to-neuron ratio?
1:1
83What does glia ratio depend on?
Brain region
84Main glial types?
Astrocytes, microglia, ependymal, oligodendrocytes
85What do astrocytes regulate?
Ions, nutrients
86What do astrocytes form?
Neural network
87What do microglia act as?
Immune cells
88What do microglia do?
Phagocytosis
89What do ependymal cells make?
Cerebrospinal fluid
90What do oligodendrocytes produce?
Myelin
91What are ions?
Charged atoms
92How do ions cross membranes?
Ion channels
93What do ion channels do?
Act like gates
94What changes voltage?
Ion movement
95Resting potential of neuron?
-70 mV
96More negative inside or outside?
Inside
97What causes depolarization?
Less negative voltage
98What causes hyperpolarization?
More negative voltage
99What opens ion channels?
Voltage threshold
100What is an action potential?
Electrical impulse
101Where does an action potential go?
Down the axon
102What is a synapse?
Neuron junction
103What does a synapse include?
Axon, dendrite, cleft
104When was the synaptic cleft verified?
1950s
105How do neurons communicate?
Neurotransmission
106What crosses the synapse?
Neurotransmitters
107What triggers calcium channels?
Action potential
108What enters at axon terminal?
Calcium ions
109What binds to vesicles?
Calcium ions
110What releases neurotransmitters?
Vesicle fusion
111Where are neurotransmitters released?
Synaptic cleft
112What refills vesicles?
Soma
113What types of neurotransmitters exist?
Amino acids, peptides
114Where are small neurotransmitters made?
Axon terminal
115Where are peptides made?
Cell body
116What organelle packages peptides?
Golgi apparatus
117What carries vesicles down axon?
Kinesins
118What guides kinesins?
Microtubules
119What is postsynaptic density?
Receptor-rich region
120What do neurotransmitters bind?
Receptors
121What do receptors control?
Ion channels
122What mops up excess transmitters?
Astrocytes
123Why mop neurotransmitters?
Prevent overactivation
124What are ionotropic receptors?
Channel-linked receptors
125How do ionotropic receptors work?
Change shape
126What are metabotropic receptors?
Indirect receptors
127What do metabotropic receptors trigger?
Biochemical cascade
128How long do neurotransmitters bind?
Short time
129What is reuptake?
Reabsorption by axon
130What do excitatory neurotransmitters do?
Depolarize dendrites
131What do inhibitory neurotransmitters do?
Hyperpolarize dendrites
132Most common excitatory transmitter?
Glutamate
133Most common inhibitory transmitter?
GABA
134Glutamate receptor types?
AMPA, NMDA
135AMPA receptors act
Fast, brief
136NMDA receptors act
Slowly
137GABA receptor types?
Ionotropic, metabotropic
138Ionotropic GABA channels
Chloride entry
139Metabotropic GABA channels
Potassium exit
140What do both GABA types cause?
Inhibition
141What do neurons have?
Receptors
142Types of receptor signals?
Hormones, modulators
143What are endocannabinoids?
Suppress neurotransmitters
144What are prostaglandins?
Increase pain sensitivity
145How do signals begin?
Molecule binds receptor
146Surface receptor pathway?
Shape change
147What do intracellular pathways change?
Ion balance, enzymes
148Where are steroid receptors?
Inside soma
149What can steroid-receptor complexes do?
Act as transcription factors
150Where do they bind?
Specific genes
152How do neurons differ?
Transmitters, receptors
153What is gene expression?
Gene activity differences
154What causes gene expression changes?
Chromatin structure
155What is chromatin?
DNA + proteins
156Open chromatin means?
Gene active
157Tightly packed chromatin?
Gene off
158Are chromatin changes reversible?
Yes
159What causes chromatin changes?
Hormones, environment
160What are alleles?
Gene variants
161What do alleles affect?
Protein function
162Example of allele disease?
Tay-Sachs
163What does Tay-Sachs affect?
Fat metabolism
164What causes Tay-Sachs?
Enzyme mutation
165Future of brain disorder study?
Genome sequencing