mod 1.4a-c reading quiz (PSYCH)

ancient Greek physician ___ correctly located the mind in the brain

• his contemporary, ___, thought it was sited in the heart

ancient Greek physician Hippocrates correctly located the mind in the brain

• his contemporary, Aristotle, thought it was sited in the heart

phrenology

• the studying of bumps on the skull — the belief it could reveal a person’s mental abilities + character traits

• proposed by Frank Gall, German physician

  • disproven / primitive method today

  • succeeded in focusing attention on the localization of function — the idea that various brain regions have particular functions (though, not the functions Gall proposed)

biological psychology

• the scientific study of the links between biological (genetic, neural, hormonal) + psychological processes

  • biological psychologists’ different names

    • behavioral neuroscientists

    • neuropsychologists

    • behavior geneticists

    • physiological psychologists

    • biopsychologists

biopsychosocial approach

• an integrated approach that incorporates biological, psychological, and social-cultural levels of analysis

  • we are biopsychosocial systems

what 3 levels of analysis does the biopsychosocial approach integrate

• biological

• psychological

• social-cultural

levels of analysis

the differing complementary views, from biological to psychosocial to social-cultural, for analyzing any given phenomenon

neuroplasticity

• the brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

  • greatest in childhood, but persists throughout life

  • enables us, more than other species, to adapt to our changing world

    • London’s taxi driver trainees who spend years learning + remembering the city’s 25,000 street locations + connections are rewarded w/ better income + enlarged hippocampus

    • well-practiced pianists are rewarded with a larger-than-usual auditory cortex area, a sound processing region

T or F — the brain you were born in is not the brain you will die in

true

T or F — even limited practice times cannot produce neural benefits

false

__ said a brain simple enough to be fully understood is too simple to produce a mind able to understand it

John Barrow

how were early explorers mapping the brain?

by localizing brain functions through early case studies

• ex

  • damage to one side of the brain = numbness / paralysis on opposite side — suggests the body’s right side is wired to the brain’s left side, vise versa

  • damage to the back of brain = disrupted vision

  • damage to left-front part of brain = speech difficulties

lesion

• tissue destruction

  • brain lesions may occur naturally (from disease or trauma), during surgery, or experimentally (using electrodes to destroy braincells)

T or F — unlike early explorers, scientists now can selectively lesion tiny clusters of normal / defective braincells to observe any effect on brain function

true

• studies revealed that damage to one area of a rat’s hypothalamus reduces eating to the point of starvation, while damage to another area produces overeating

3 ways today’s neuroscientists can stimulate brain parts (aside from lesions)

• electrically

• chemically

• magnetically

in order to note effect

modern electrodes can __ (2)

• detect the electrical pulse in a single neuron

  • ex: detects exactly where the info goes in a rat’s brain when someone tickles its belly

• eavesdrop on chatter of billions of neurons

optogenics

• a technique allowing neuroscientists to control the activity of individual neurons

  • ex: programming neurons to become receptive to light can help researchers determine / examine biological bases of

    • sensations, fear, depression, substance abuse disorders

electroencephalography (EEG)

• electrodes placed on scalp

• measures electrical activity in neurons

• an amplified recording of the waves of electrical activity sweeping across brain’s surface

  • waves are measured by electrodes placed on scalp

  • brainwaves recorded through shower-cap-like hat filled w/ electrodes covered w/ constructive gel

    • studying EEG is like studying a blender’s motor by listening to its hum

    • researchers can present a stimulus repeatedly + filter out brain activity unrelated to stimulus

MEG (magnetoencephalography)

• a head coil

• measures magnetic fields from brain’s natural electrical activity during certain tasks

  • head coil like salon hair dryer that participants sit under

  • special rooms to isolate brain’s magnetic fields + cancel out other magnetic signals (ex: Earth’s magnetic field)

  • participants complete activities —> tens of thousands of neurons generate electrical pulses —> create magnetic fields —> speed + strength of magnetic fields enable research to understand how certain tasks influence brain activity

CT (computed tomography)

• X-rays of the head generate images that may locate brain damage

  • a series of X-ray photos taken from different angles + combined by computer into a composite representation of a slice of the brain’s structure

PET (position emission tomography)

• technique for detecting brain activity that displays where a temporarily radioactive form of glucose goes while the brain performs a given task

  • depicts brain activity by showing each brain area’s consumption of its chemical fuel — sugar glucose

  • monitors while participants do math, look @ face images, daydreams

  • brain = ~2% body weight, but consumes 20% of calorie intake

brain is ~ __% body weight, but consumes _% of calorie intake

brain = ~2% body weight, but consumes 20% of calorie intake

MRI (magnetic resonance imaging)

• a technique where people sit / lie down in a chamber that uses magnetic fields + radio waves to provide a map of rain structure

  • computer generated images of soft tissue

  • head put into strong magnetic field, aligns spinning atoms in brain molecules

  • radioactive pulse momentarily disorients atoms —> when back to normal spins, signals omitted to provide detailed picture of soft tissues, including brain

    • ex: enlarged ventricles (fluid filled brain areas) in some people w/ schizophrenia; larger neural area in left hemisphere of musicians

CT vs MRI

• CT

  • X-ray photos that are composited into 3d image

  • generally better at distinguishing between the internal structures of the body

• MRI

  • magnetic waves + radio waves used to produce images

  • generally better at distinguishing between different types of tissue in the body

fMRI (functional MRI)

• special application of MRI

• by comparing continuous MRI scans, it measures blood flow to brain regions

• reveals blood flow —> brain function + structure

  • where brain is active, blood goes

fNIRS (functional near-infrared spectroscopy)

• shines infrared light on blood molecules to identify brain activity

  • equipment can fit in large backpack, enabling researchers to study biology of mind in difficult-to-reach populations

__% accuracy of neuroscience team when identifying which activities the study participants were doing when 129 people’s brains were scanned while doing 8 different tasks

80% accuracy

T or F — today’s techniques for peering into brain are doing for psychology what microscopes did for biology + telescopes did for astronomy

true

T or F — learning about neurosciences now is like studying world geography when Magellan explored the seas

true

__ said, “individually, we contribute little or nothing to the truth. by the union of all a considerable amount is amassed”

Aristotle

vertebrate brain’s 3 divisions

• hindbrain

• midbrain

• forebrain

hindbrain

• contains brainstem structures that direct essential survival functions

  • breathing, sleeping, wakefulness, arousal, coordination, balance

• consists of medulla, pons, cerebellum

what 3 structures does the hindbrain contain

• pons

• medula

• cerebellum

midbrain

• connects hindbrain w/ forebrain

• controls some motor movement

• transmits auditory + visual information

  • atop the brainstem

forebrain

• manages complex cognitive activities, sensory associative functions, and voluntary motor activities

  • consists of the cerebral cortex, thalamus, hypothalamus

T or F — organisms’ brains have evolved to suit their environment

• true

  • humans have extremely developed forebrains — ability to make complex decisions + judgements

  • predator sharks have complex hindbrains — ability to hunt prey

brainstem

• responsible for automatic survival functions

• a crossover point where most nerves to and from each side of the brain connect w/ the body’s opposite side (contralateral hemispheric organization)

• the brain’s innermost region

  • the central core of the brain, beginning where the spinal cord wells as it enters the skull

• contains pons, medulla, reticular formation, midbrain

4 structures the brainstem contains

• pons

• medulla

• reticular formation

• midbrain

medulla

• the hindbrain structure that is the brainstem’s base

  • slight swelling in the spinal cord just after it enters the skull

• controls heartbeat + breathing

  • a conscious mind is not needed to orchestrate our hearts’ pumping + lungs breathing as seen in brain-damaged patients in vegetative state — brainstem handles that task

pons

• helps coordinate movements + control sleep

  • just above the medulla

  • the largest part of brainstem

thalamus

• egg-shaped structures that act as brain’s sensory control center

• forebrain’s sensory control center

• sits atop the brainstem

• directs messages to sensory receiving areas in the cortex + transmits replies to the cerebellum + medulla

  • receives info from all sense EXCEPT smell, routes them to respective regions

  • similar to a train station (what Seoul is to SK’s trains)

__ is what the thalamus being to sensory info is

Seoul to South Korea’s trains — a hub through which traffic passes en route to various locations

reticular formation

• a nerve network that travels through the brainstem into thalamus

  • inside brainstem, between your ears

  • extends from spinal cord —> thalamus

• filters info + pays an important role in controlling arousal / state of alertness

  • nerve network governed by reticular activating system

  • Giuseppe Moruzzi + Horace Magoun discovered that the reticular formation also controls arousal / state of alertness

• as spinal cord’s sensory input flows up to thalamus, some travels through reticular formation, which filters incoming stimuli + relays important info to other brain areas

who discovered that the reticular formation also controls arousal / state of alertness? + how?

• Giuseppe Moruzzi + Horace Magoun discovered that the reticular formation also controls arousal / state of alertness in 1949

  • electrically stimulated sleeping cat’s reticular formation, almost instantly became awake + alert

  • Magoun severed a cat’s reticular formation w/out damaging nearby sensory pathways — the cat lapsed into a coma + never woke up

cerebellum

• the hindbrain’s “little brain” @ rear of brainstem

• processes sensory input, coordinates movement output + balance, enables learning + nonverbal learning

  • contains over half of the brain’s neurons, operates just outside awareness

  • cerebellum + basal ganglia are both deep brain structures involved in motor movement

  • coordinates voluntary movement w/ pons

    • involved when a soccer player masterfully controls the ball

    • coordination suffers under alcohol’s influence

which brain structure contains over half of the brain’s neurons

cerebellum

T or F — injured cerebellum = difficulty walking, keeping balance, texting a friend

• true

  • jerky / exaggerated

  • cannot be dancer/guitarist

T or F — our brain processes most information within our awareness

• false

  • our brain processes most information outside our awareness

    • we are aware of the results of our brain’s labor, but not how we construct the visual image

limbic system

• associated w/ emotions, drives, memory formations

• neural system located mostly in forebrain — below cerebral hemispheres

  • consists of amygdala, hypothalamus, hippocampus, thalamus, pituitary gland

  • can thank limbic system for the emotion when we enjoy a joke

what 5 structures reside in the limbic system

• amygdala

• hypothalamus

• hippocampus

• thalamus

• pituitary gland

amygdala

• two lima-bean-sized neural clusters in limbic system

• linked to emotion

• enables aggression + fear

  • people with amygdala lesions displayed reduced arousal to fear + anger-arousing stimuli

  • animals’ electrically stimulated amygdala illicited fear + anger response

amygdala lesion + stimulation case studies

• Heinrich Kluver + Paul Rucy made an ill-tempered rhesus monkey —> mellow creature after an amygdala lesion in 1939

  • people with amygdala lesions display reduced arousal to fear + anger arousing stimuli

• patient S.M. (woman w/ lesion) — “the woman with no fear”, even when threatened w/ gun

• stimulating one part of a cat’s amygdala illicits its attack response, while stimulating another part makes it cower in fear when locked in the same cage as a small mouse

  • electrically stimulating amygdala of normal animal illicits anger + fear responses

T or F — monkeys + humans w/ amygdala damage become less fearful of strangers

• true

  • people w/ amygdala lesions display reduced arousal to fear + anger arousing stimuli

T or F — criminal behavior is linked to amygdala dysfunction

true

T or F — the brain is neatly organized into structures that correspond to behavior categories

• false

  • the brain is not neatly organized into structures that correspond to behavior categories

    • ex: the amygdala is engaged with other mental phenomena

      • being afraid / aggressive occurs in many brain areas (not just amygdala)

    • ex: if you destroy a car battery, it won’t run; but battery is just one link in an integrated system

hypothalamus

• linked to emotion + reward

• helps govern endocrine system

• directs several maintenance activities (eating, drinking, body temp)

  • important link in command chain governing bodily maintenance

• a limbic system neural structure lying below (hypo) the thalamus

  • neural clusters in the hypothalamus influence different functions

  • together, they help maintain a steady (homostatic) internal state

  • later experiments locate other “pleasure centers” / reward centers

  • other limbic system reward centers in other species — ex: dolphins + monkeys have nucleus accumbens in front of hypothalamus

T or F — animals come equipped w/ built-in systems that reward activities essential to survival

• true

  • animal research has revealed general dopamine-related award systems + specific centers associated w/ pleasures (eating, drinking, sex)

  • “if you were designing a robot vehicle to walk into future + survive, you’d wire it up so that behavior that ensured survival of the self or species — like sex and eating — would be naturally reinforcing”

T or F — stimulating brain’s hedonic hot spots (reward circuits) produces more desire than enjoyment

• true

  • some evidence indicates that humans have limbic centers for pleasure

  • when electrodes implanted in violent patients’ reward center areas, they only reported mild pleasure

    • unlike Olds + Milners’ rats, patients are not driven to frenzy

T or F — disorders may stem from malfunctions in natural brain systems for pleasure + well being

• true

  • people genetically predisposed to this reward deficiency syndrome may crave whatever provides missing pleasure / relieves negative feelings (ex: aggression, rich food, drugs, alcohol)

hippocampus

• a neural center in limbic system that helps process explicit (conscious) memories (of facts + events) for storage

• a curved brain structure

  • lost hippocampus = lost ability to form new memories of facts + events

    • those who survive hippocampal brain tumor in childhood struggle to remember new information as adult

    • NFL players to experiences over one loss-of-consciousness concussions may latter have shrunken hippocampus + poor memory

    • size + function of hippocampus decreases as we grow older, furthers cognitive decline

corpus callosum

• the large band of neural fibers connecting the two brain hemispheres + carrying messages between them

• allows left + right hemispheres to relay information with each other

  • people with severed corpus callosum don’t possess this communication

cerebral cortex

• the surface layer / intricate fabric of interconnected neural cells covering the forebrain’s cerebral hemispheres

• body’s ultimate control + information processing center

  • cortex means “bark” — scholars used Latin + Greek words as graphical descriptions

  • contains ~ 20-23 billion of the brain’s nerve cells + 300 trillion synaptic connections

  • mammals’ complex cerebral cortex offers high capacity for learning + thinking, enabling adaptations to ever changing environments

    • what makes humans distinct is the size + interconnectivity of our cerebral cortex

what distinguishes humans most from other animals?

our cerebral cortex

cerebrum

• the 2 central hemispheres that contribute 85% of the brain’s weight

• enables our perceiving, thinking, speaking

  • cerebral hemispheres come as a pair (like other brain structures — thalamus, hippocampus, amygdala)

  • covered by cerebral cortex

what contributes 85% of the brain’s weight

the cerebrum (brain’s 2 central hemispheres)

structure of cortex

• makes brain appear as a wrinkled organ, shaped like oversized walnut

  • w/out wrinkles, flattened cerebral cortex would require 3x the area — around the size of large pizza

• brain’s left + right hemispheres filled mainly w/ axons connecting cortex to brain’s other regions

• many functions require the interplay of several lobes

  • frontal lobes, parietal lobes, occipital lobes, temporal lobes

names of 4 lobes

• frontal lobes

• parietal loes

• occipital lobes

• temporal lobes

name…

1) frontal lobe

2) parietal lobe

3) temporal lobe

4) occipital lobe

frontal lobe

• enables linguistic processing, muscle movements, higher order thinking, executive function (ex: making plans + judgements)

  • the portion of the cerebral cortex lying just behind the forehead

parietal lobes

• receives sensory input for touch + body position

  • the portion of the cerebral cortex lying @ top of the head + toward the ear

occipital lobes

• includes areas that receive information from the visual fields

  • the portion of the cerebral cortex lying @ back of head

temporal lobes

• enables language processing

• includes the auditory areas, each of which receives information primarily from opposite ear

  • the portion of the cerebral cortex lying ~ above the ears

motor cortex

• a cerebral cortex area @ the rear of the frontal lobes that controls voluntary movements

  • the brain devotes more tissue to sensitive areas + areas requiring precise control — finger have greater representation in cortex than your upper arm

  • discovered by German physicians Gustav Fritsch + Eduard Hitzig in 1870

    • used mild electrical stimulation to parts of an animal’s cortex to make parts of its body move — effects were selective

      • stimulation caused movement when applied to arch-shaped region @ back of frontal lobe, running ear-to-ear across top of brain

      • stimulating parts of this region in left / right hemisphere caused movements of specific body parts on opposite side of body

how can scientists predict a monkey’s arm motion just before it moves?

by repeatedly measuring motor cortex activity preceding specific arm movements

2 case studies of how scientists can determine if a person w/ paralysis can move a robotic limb by stimulation of the brain

• 100 tiny recording electrodes implanted into motor cortexes of 3 monkeys

  • gained rewards by using joystick to follow a moving red target —> matched brain signals w/ arm movement —> programmed a computer to monitor signals + operate joystick

  • resulted in mind-reading computer — monkey thinking about a move led to cursor moving w/ proficiency

• Ian Burkhart’s legs + arms paralyzed; by learning his unique brain response patterns, the computer can predict his brain activity to help make movements

  • through implanting recording electrodes in his motor cortex

  • similarly, prosthetic voices created by reading the brain’s motor commands that direct vocal movement

somatosensory cortex

• a cerebral cortex area @ the front of the parietal lobes that registers + processes body touch + movement sensations

• parallel to + just behind the motor cortex

• specializes in receiving information from skin senses (touch, temperature) + movement

  • the more sensitive the body region, the larger the somatosensory cortex area devoted to it

    • ex: humans’ supersensitive lips project to larger brain area than toes to kiss; rats’ whisker sensations; owls’ hearing sensations

motor cortex vs somatosensory cortex

• motor cortex : output

• somatosensory cortex: input

which lobe is the visual cortex located in

occipital lobes

• visual info you receive —> visual cortex in occipital lobes

• visual information travels from occipital lobes —> other areas that specialize in tasks (identifying words, detecting emotions, recognizing faces)

  • if stimulated in occipital lobes, might see flashes of light/dashes of color (w/ normal vision)

  • LSD increases communication between visual cortex + other regions

    • produced visual hallucinations

which lobe is the auditory cortex in

temporal lobes

• auditory info you receive —> auditory cortex in temporal lobes

• auditory info travels a circuitous route from one ear —> auditory receiving area above opposite ear

  • if stimulated in auditory cortex, you might hear a sound

    • tinnitus in one ear is associated w/ activity in temporal lobe on brain’s opposite side

    • fMRI scans of people with schizophrenia has active auditory areas in temporal lobes

• small cortical areas that either receive sensory input or direct muscular output occupy ~ __ of brain’s cerebral cortex

  • remaining vast regions of cortex are ___ areas

• small cortical areas that either receive sensory input or direct muscular output occupy ~ ¼ of brain’s cerebral cortex

  • remaining vast regions of cortex are association areas

association areas

• areas of the cerebral cortex that are not involved in primary motor / sensory functions

• involved w/ higher mental functions (learning, remembering, thinking, speaking)

• interprets, integrates, and acts on sensory info + links them w/ stored memories

  • electrically probing an association area will NOT trigger any observable response

  • cannot be neatly mapped

  • found in all 4 brain lobes

  • more intelligent animals have larger association areas

prefrontal cortex

• frontal lobe

• enables judgement, planning, social interactions, processing of new memories

• in forward part of frontal lobes

  • people w/ damage to this area may have high intelligence test scores + great cake-baking skills; but wouldn’t be able to plan ahead to begin baking a cake for a party; if they did begin to bake, they might forget the recipe; if responsible for the absence of cake, may feel no regret

T or F — frontal lobe damage can alter personality, remove a person’s inhibitions, and leads to unrestrained moral judgements

• true

  • Phineas Gage, 1848: survived a rod up through his left cheek + out top of his skull, leaving frontal lobes damaged

    • quick recovery, HOWEVER, frontal lobes + brain regions that control emotion + decision making connections were damaged

    • drastic personality change, most mental abilities + memories intact

  • frontal lobes help w/ moral compass

T or F — parietal lobes (association area) enable math + spacial reasoning

• true

  • large + unusually shaped in Einstein’s normal weight brain

  • when stimulated, patients had a desire to move their body part but didn’t

    • when further stimulated, patients thought they had moved their body part but didn’t

    • when stimulated in an association area in the frontal cortex near the motor area, they moved but didn’t know they had

      • suggests that our perception of moving flows not from the movement itself, but rather from our intention

what happens if association area on underside of right temporal lobe is damaged?

• it enables face recognition

• if damaged, you will be unable to identify the person even if they’re very familiar to you

T or F — our mental experiences + psychological health rely on coordinated brain activity

true

T or F — complex mental functions don’t reside in any single place

true

T or F — neuroplasticity is how our brain adapts to new situations

• true

  • may occur after serious damage, especially in young children (whose undamaged hemisphere develops extra connection)

  • helps explain why some deaf people (who learned sign language before another language) may have enhanced peripheral motor detection vision

T or F — some neural tissue can reorganize in response to damage

true

T or F — blindness / deafness makes unused brain areas available for other uses, such as sound + smell

• true

  • if a blind person uses one finger to read braille, the brain area dedicated to that finger expands as sense of touch invades the visual cortex that normally helps people see

when can brain function reassignment occur?

may occur when disease / damage frees up other brain areas normally dedicated to specific functions

how does brain often attempt self-repair? (2)

• by reorganizing existing tissue

• potentially though neurogenesis — producing new neurons

neurogenesis

the formation of new neurons

lateralization

the brain’s left + right hemispheres serving different functions

why did research spanning over a century conclude that the right hemisphere was significantly minor?

• the left hemisphere’s accidents, strokes, and tumors impair reading, writing, speaking, math, and understanding

  • similar right-hemisphere injuries have less visibly dramatic effects, leading researchers to believe it was “minor”

what happened after 2 neurosurgeons speculated that severing the corpus callosum would stop major epileptic seizures — caused by amplification of abnormal brain activity bouncing back and forth between hemispheres?

• seizures disappeared, surprisingly healthy, personality + intellect hardly affected

• however, since communication lines between hemispheres severed, both hemispheres express themselves individually

  • information sharing doesn’t take place

split brain

a condition resulting from surgery that separates the brain’s 2 hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them

how sensory information is processed through 2 hemispheres

• each eye receives sensory information from entire visual field

• in each eye, information from left field of vision —> right hemisphere; information from right half of visual field —> left hemisphere (usually controls speech)

  • information received by either hemisphere is quickly transmitted to the other across the corpus callosum

explain the early experiment conducted by Gazzaniga (1967) on split-brain patients

• asked patients to stare @ dot as he flashed HE o ART on a screen

  • HE appeared in left visual field —> transmitting to right hemisphere

  • ART appeared in right visual field —> transmitting to left hemisphere

• asked patients to say (controlled by left hemisphere) what they had seen: reported ART

• when asked to point w/ their left hand (controlled by right hemisphere) to what they had seen, they pointed to HE

roles of hemispheres

• left hemisphere

  • in charge of speaking

  • skilled @ making quick, literal interpretations of language

• right hemisphere

  • excels @ making inferences, helps modulate speech to make meaning clear, helps orchestrate our self-awareness