Exam 3 Intraspecific variation

65 million

primates originated roughly _______ million years ago

Encephalized

humans are the most ________ species

Glires (rodents and rabbits)

At their body size, primates have 2x larger brains than _______

fossil skulls

one can estimate brain size from ____________

Endocranial cavity

the cavity within the skull in which the brain is housed

1.5-2 million years ago

Absolute brain size increased roughly ______

150,000 years ago

brain increased again roughly _________ as HOMO sapiens emerged. (tripled as modern humans evolved from early hominids)

Growth spirt #1

early hominids, correlates (roughly) with the taming of fire

Growth Spirt #2

onset of homo sapiens. Intraspecific competition for resources and mates

Neocortex, brainstem

the proportional size of the _________ increases predictably as overall brain size INCREASES, while the ____________ proportionally SHRINKS. first one comprises 80% of brain mass

Frontal lobe, occipital lobe, temporal

3 neocortical lobes

prefrontal cortex

becomes disproportionately larger as neocortex increases.

comprises nearly 30% of the entire neocortex in humans

Response inhibition and working memory

the prefrontal cortex is involved in....

Isotropic fractionation

it involves homogenizing brain tissue and counting the number of nuclei in a cell suspension to obtain an estimate of the number of neurons

Neurons

__________ numbers increases predictably with brain weight

More

Large primates brains contain ________ neurons than equally large rodents brains

Cerebellum

the highest proportion of neurons is found in the ____________

Language

_______ is arguably our most distinctive attribute as a species

Broca's aphasia

an inability to articulate speech

Patient "Tan"

able to comprehend speech and could physically move lips and tongue, but could not speak any other word but "tan"

Broca's area

a cortical region in the frontal lobe of the human brain with functions linked to speech production. (lesion on the posterior portion of the left inferior prefrontal cortex)

Language comprehension

Damage to posterior portions of the superior temporal love impairs _______ _________ without impairing speech

network of cortical areas

Language is likely supported by a widespread.......

left hemisphere dominant

only the late stages of speech are......

Dorsal Stream

speech production

Ventral Stream

language comprehension

Parkinson's and schizophrenia

Men are more likely to be diagnosed with _____ and _____

Depression

Women are more likely to be diagnosed with different forms of ________

zebra finch

male ______ sing very complex song to attract females, the females do not sing

song system

the network of brain regions that help them learn and produce these songs.

Are much larger in males than in females

sexually dimorphic nucleus (SDN)

a cell group in the preoptic area of rodents that is significantly larger in males than in females. (in males involved in sexual behaviors such as ejaculation)

Anteroventral periventricular nucleus (AVPV)

a cell group in the preoptic area that is larger in females than in males. Helps trigger ovulation.

more numerous

Dopaminergic neurons in the substantia nigra are _______ _______ in females than in males

Substantia nigra (SNc)

projects mainly to the dorsal striatum and releases dopamine

testosterone may be slightly toxic to dopaminergic neurons, while estrogen is not

Why are men more likely to develop Parkinson's than women?

neocortical neurons

Men tend to be taller than women and have more ______ _______

cortical gray matter, corpus callosum

compared to men, women tend to have proportionately more _______ and a proportionately larger ________

Intraspecific difference

a difference existing within a species or between individuals of a single species

Visual ability

retina to lateral geniculate nucleus to primary visual cortex (V1)

grow

Human brains continue to ______ for several years after birth

___________ surface area triples between birth and young adulthood, primarily due to myelination

synapses and the expansion of dendritic trees

Neocortical gray matter also increases in volume, mainly due to the addition of more.....

Delayed maturation

expansion and maturation are delayed in the prefrontal, parietal, and lateral temporal lobes.

Maybe why teenagers are most likely to take risks than adults

Girls, Boys

Gray matter volume peaks in _____ at 8.5 years of age; in _____ this peak is reached two years later

age 50

Brain volume remains the same until about around.....

cerebral ventricles

decrease in brain volume coincides with an increase in the size of the......

0.5%

in healthy people between ages 60 and 90, many neocortical regions shrink by _____ per year

amygdala and hippocampus

most age-related differences, outside the neocortex, are in the......

white matter as well as some neurons and synapses

as aging brains shrink in volume, the lose substantial amounts of........

Alzhiemer's Disease

a neurodegenerative disease that is associated with progressive dementia and the loss of synapses (and eventually neurons) in diverse brain regions. Characterized by amyloid plaques and neurofibrillary tangles

Early Stage of Alzheimer's Disease

mild inability to form new episodic(long term) memories

Late Stage of Alzheimer's Disease

old memories are lost, mood wings become more severe, and thought become confused

synapses

plaques and tangles destroy_____ and eventually kill neurons

Hippocampus and entorhinal cortex

Cholinergic neurons of the basal forebrain and the noradrenergic neurons in the locus coeruleus

main regions vulnerable to Alzheimer's disease