Chapter7&8 Flashcards
(197 cards)
1
Q
Average brain weight of a newborn?
A
370 grams
2
Q
Average weight of an adult brain?
A
3 pounds
3
Q
Number of neurons in an adult brain?
A
86 billion
4
Q
Duration of brain development in womb?
A
40 weeks
5
Q
What is the brain growth rate immediately after birth?
A
1 percent per day
6
Q
What is the brain growth rate at 3 months?
A
0.4 percent per day
7
Q
By 90 days old, how much is brain volume larger?
A
64 percent larger
8
Q
Which brain region grows the fastest?
A
Cerebellum
9
Q
Why is the cerebellum important for babies?
A
Learning motor skills
10
Q
What contributes to the overall increase in brain volume?
A
Brain cells growing and connecting
11
Q
By what percentage does the number of neurons in the cortex increase during the first three months of life?
A
23–30 percent
12
Q
What process involves neurons making many connections?
A
Synaptogenesis
13
Q
What are the distinct differences found in the gray matter of young people and adolescents?
A
Density, volume, mass, thickness
14
Q
When does the brain reach about 90% of its adult size?
A
Childhood
15
Q
What increases rapidly during the first couple years of life?
A
Synaptic density
16
Q
How many more synapses does a 2-year-old’s brain have compared to an adult’s?
A
50% more
17
Q
What percentage is a 2-year-old’s brain of an adult brain size?
A
0.8
18
Q
What is synaptic pruning?
A
Reduction of synapses
19
Q
When does synaptic pruning occur?
A
Early childhood
20
Q
What shapes synaptic pruning?
A
Toddlers’ experiences
21
Q
What is the purpose of synaptic pruning?
A
Strengthen active synapses
22
Q
How developed are human baby brains at birth?
A
Less developed than other animals
23
Q
When do squirrel monkeys reach adult brain size?
A
6 months old
24
Q
When do human brains develop extensively?
A
After birth
25
What shapes developing brains?
Environment and experience
26
What provides sensory inputs for babies?
Seeing parents, hearing voices
27
What affects brain development during critical periods?
Sensory, motor, emotional inputs
28
What influences learning and behavior during critical periods?
Genes and environment
29
What processes shape neural connections?
Neuronal cell death and synaptic pruning
30
When do high rates of learning occur?
During critical periods
31
What happens to the brain during adolescence?
Capacity to learn
32
How is the teenage brain described?
Like clay, very messy
33
What process occurs during synaptic pruning?
Competitive elimination
34
What neurological changes occur in the brain during aging?
Dendritic branches extend, myelination increases
35
Why are longitudinal studies important?
Reveal long-term effects of early life
36
What is adolescence considered in brain development?
Second critical period
37
What changes occur in the brain during adolescence?
Increase in white matter volume
38
What connects the brain's right and left hemispheres?
Corpus callosum
39
What explains enhanced learning capacity in adolescence?
Growth of the corpus callosum
40
What contributes to teenage behaviors?
Changes in brain connections
41
Which brain regions are involved in teenage behavior changes?
Frontal and limbic
42
What can increase the risk of addiction?
Risk taking and sensation seeking
43
How is addiction viewed by some?
Acquired learning disorder
44
What brain functions are affected by frequent drug use?
Memory, attention, executive functioning
45
What brain area matures during adolescence?
Cerebral cortex
46
What does the blue color indicate in the brain development image?
More mature areas
47
What is important for reasoning and abstract thinking?
Cerebral cortex
48
What imaging technique shows changes in gray and white matter due to alcohol in adolescents?
Diffusion tensor imaging (DTI)
49
What were the effects of binge drinking on brain activity in adolescents?
Lower activity, less attention
50
What was reduced in adolescents who used alcohol?
Gray matter volume, white matter integrity
51
At what age does the human brain continue to develop?
About 30 years old
52
What happens to gray matter density in most brain regions with age?
Declines
53
In which brain region does gray matter density increase until age 30?
Left temporal lobe
54
What is myelination?
Conducts electrical signals
55
Where are early myelination areas?
Visual, auditory, limbic cortices
56
What areas become myelinated closer to 30?
Frontal, parietal neocortices
57
What cognitive functions improve with myelination?
Working memory, higher functions
58
What is the last brain region to develop?
Frontal lobe
59
What is the function of the frontal lobe?
Executive functioning
60
What might explain typical teenager characteristics?
Late maturation of frontal lobe
61
What is plasticity?
Brain's ability to adapt
62
Why are critical periods important?
Allows brain to modify itself
63
Is plasticity unique to humans?
No
64
What is experience-expectant plasticity?
Integrating environmental stimuli
65
What is essential for healthy brain maturation?
Exposure during critical periods
66
Examples of experience-expectant stimuli?
Hearing language, seeing faces
67
What happens to finches that do not hear adult songs?
Learn to sing poorly
68
What does experience-dependent plasticity describe?
Changes from life experiences
69
Experience-dependent plasticity occurs when?
During critical periods and adulthood
70
What do recent insights into brain development promise?
New treatments for disorders
71
What could help understand aging?
Brain development insights
72
What might correct problems from mistimed critical periods?
Manipulating adult plasticity
73
Importance of understanding normal brain function during development
Key to finding age-specific therapies for brain disorders
74
Brain changes during development: overall size
Increases
75
Brain changes during development: number of cells
Increases
76
Brain changes during development: myelination
Increases
77
Brain changes during development: synapse formation
Increases
78
Continued brain development
Beyond teenage years
79
What happens to brain connections over time?
Strengthen and myelin increase
80
When does the brain's white matter reach peak volume?
Around age 40
81
What characterizes brain networks during childhood and adolescence?
Locally organized
82
What contributes to the increase in white matter?
Increased connections
83
What is the most important brain area to become fully wired in adulthood?
Prefrontal cortex
84
What abilities are important for cognitive control?
Suppressing impulses
85
How do adult brains compare to adolescent brains in cognitive control?
Better wired for control
86
When does intelligence peak?
Ages 25 to 60
87
When does fluid intelligence peak?
around age 30
88
When does crystallized intelligence peak?
around age 50
89
What includes problem solving and pattern identification?
fluid intelligence
90
What deals with vocabulary and factual knowledge?
crystallized intelligence
91
What is aging characterized by?
Resilience in health
92
What increases the risk during aging?
Injury and disease
93
What is dementia?
Cognitive decline
94
What wraps around axons to speed up electrical transmission?
Myelin
95
What are the exposed areas of myelinated axons called?
Nodes of Ranvier
96
What lifestyle choices support cognitive health?
Diet and exercise
97
What is the most common cognitive change with aging?
Memory decline
98
Which type of memory declines with age?
Declarative memory
99
What types of memory remain largely intact?
Nondeclarative memory
100
What does nondeclarative memory include?
Procedural memory
101
What is working memory?
Hold and manipulate info
102
At what age does working memory decline?
Starts at age 30
103
What type of intelligence is working memory an example of?
Fluid intelligence
104
What decreases with age related to fluid intelligence?
Processing speed, problem-solving
105
What becomes harder as our brains age?
Focusing in noise
106
What is selective attention?
Focus on one stimulus
107
What does divided attention refer to?
Focus on two tasks
108
What affects split focus with age?
Conversation while driving
109
What begins to decline in midlife?
Total brain volume
110
When does brain volume decline accelerate?
Around age 60
111
Which brain regions show the biggest volume losses with aging?
Prefrontal cortex, cerebellum, hippocampus
112
What are the changes at the neuron level in aging brains?
Shrinking neurons, retraction of dendrites, loss of myelin
113
Do all areas of the brain shrink uniformly with age?
No, some areas shrink more, faster
114
What primarily drives volume loss in adolescence?
Synaptic pruning and cell death
115
What part of the brain thins as we age?
Cerebral cortex
116
Which lobes experience pronounced thinning?
Frontal and temporal lobes
117
What areas show pronounced declines in volume and thickness?
Temporal and frontal lobes
118
What theory relates to brain aging?
Last in, first out
119
What fibers develop first in the brain?
Projection fibers
120
What type of fibers connect diffuse areas within a single hemisphere?
Association fibers
121
Which fibers are the last to reach maturity?
Association fibers
122
What aspect of the aging brain shows steep functional declines with age?
Association fibers
123
What type of changes occurs at synapses in the aging brain?
Numerous changes
124
What is believed to have a greater effect on cognitive decline in aging?
Synaptic changes
125
What alterations occur to dendrites in the aging process?
Dendrites shrink and lose spines
126
Which class of spines is targeted during aging?
Thin spines
127
How do thin spines behave compared to mushroom spines?
More plastic, extend and retract rapidly
128
What is associated with cognitive decline?
Loss of thin dendritic spines
129
What declines with age in the brain?
Formation of new neurons
130
Which regions continue neurogenesis throughout life?
Olfactory bulbs and dentate gyrus
131
How does neurogenesis change with age in mice?
Plummets with age
132
What recent studies suggest about neurogenesis in humans?
Modest decline
133
What effect does boosting neurogenesis have according to mouse studies?
Enhances cognitive function
134
What chemical changes occur with age related to neurotransmitters?
Decline in amount and receptors
135
What role does gene expression play in aging?
Changes in expression
136
How do gene expressions compare between older and younger adults?
Older adults express less
137
What signs did underexpressed genes show?
More signs of damage
138
What contributes to aging processes in the brain and body?
DNA damage accumulation
139
What are mitochondria?
Cellular power plants
140
What do metabolic reactions in mitochondria produce?
Free radicals
141
What can free radicals damage?
Fats, proteins, DNA
142
What does the body have to neutralize free radicals?
Natural defense mechanisms
143
What happens to mechanisms that protect against oxidative damage with age?
They decline
144
What accumulates in brain cells' mitochondrial DNA with age?
Damage
145
What did studies in rodents link increased oxidative damage to?
Memory impairments
146
What percentage of the body's fuel does the brain demand?
20 percent
147
What diminishes in the aging brain?
Glucose uptake
148
What declines alongside glucose uptake in aging?
Mitochondrial metabolism
149
What often occurs with metabolic changes in aging?
Immune dysfunction
150
What are microglia?
Resident immune cells
151
What jobs do microglia perform?
Defend, clean, maintain
152
What is harmful to brain health?
Prolonged inflammatory state
153
How do microglia change with age?
More reactive
154
What do reactive microglia increase?
Inflammatory response
155
What do reactive microglia dampen?
Anti-inflammatory molecules
156
What contributes to cognitive impairments according to mouse studies?
Excessive microglial activity
157
What diseases are associated with abnormal protein buildup?
Alzheimer’s and Parkinson’s
158
What process do cells use to manage damaged proteins?
Break down and recycle
159
What happens to damaged molecules in cells over time?
Build up and prevent normal functioning
160
Why are brain cells more vulnerable to damaged molecule buildup?
Not replaced as often
161
What happens to waste removal systems with age?
Reduce efficiency
162
How does poor cardiovascular health affect cognitive function?
Increased risk of cognitive impairment
163
What type of diets can reduce cardiovascular risks?
Rich in vegetables, fruits, whole grains
164
Which diets are linked to reduced cognitive decline?
Mediterranean and DASH diets
165
What dietary factors are linked to cognitive impairment?
High blood pressure, high LDL cholesterol
166
Which nutrients are linked to improved cognitive performance?
Antioxidants, omega-3 fatty acids
167
What vitamins are considered antioxidants?
Vitamins C and E
168
What have observational studies shown about these compounds?
High dietary intake is beneficial
169
What type of exercise can improve cognitive function?
Aerobic exercise
170
What benefits are associated with regular physical activity?
Improved learning and memory
171
How does physical activity relate to dementia risk?
Reduced risk
172
What effects does physical activity have on Alzheimer's disease?
Slow progression
173
What markers of brain health improve with higher physical activity?
Reduced cortical thinning
174
How does exercise provide neuroprotective effects?
Improves neuroplasticity
175
What is neurogenesis?
Formation of new nerve cells
176
What does neuroplasticity allow the brain to do?
Reorganize connections between neurons
177
How does exercise affect neurogenesis in older mice?
Increases neurogenesis rates
178
What are the effects of exercise on learning and memory in older mice?
Better performance
179
What benefits does exercise provide beyond neurogenesis?
Improves blood flow and neurotrophic factors
180
Is starting exercise later in life beneficial for humans?
Yes, beneficial
181
When is it suggested to adopt an exercise program for more benefits?
Earlier in life
182
How do mental stimulation and social networks affect cognitive function in aging?
Improve cognitive function
183
What type of environment helps mice perform better on learning and memory tests?
Cognitively stimulating environments
184
What enhances neuroplasticity?
Increased neurogenesis
185
What activities help lower cognitive decline?
Cognitive work and stimulating activities
186
What is beneficial for cognition as we age?
Active social life
187
What have neuroscientists learned about aging?
Changes in the brain
188
What do 'ups and downs' figuratively refer to?
Periods of alertness vs. relaxation
189
What are the different brain states mentioned?
Asleep, awake, aroused, relaxed
190
Who benefits from understanding sleep and alertness?
Doctors, pilots, shift workers
191
Importance of sleep for brain health?
Active brain during sleep
192
How much time do people spend sleeping?
One-third of life
193
Function of brain activity during sleep?
Solidifying memories
194
What can impair driving as much as alcohol?
Too little sleep
195
Name a health risk of long-term sleep deprivation.
Diabetes
196
What cognitive issues can sleep deprivation cause?
Cognitive impairment
197
What mental health issues are linked to lack of sleep?
Anxiety, depression
