psychology IB exam- Bio Approach

definitions and studies

techniques: MRI

Magnetic resonance imaging

creates detailed images of human body using a magnet along with radio waves

creates a magnetic field around the patient and send pulses of radio waves from scanner

strengths and weaknesses of MRIs

strengths: non-invasive and safe

• detailed image of internal structures of body

• can show the effect of psychological trauma/conditions

weaknesses: big/expensive

• excludes patients because of things like metal in bodies, weight and claustrophobia

• thermal injuries possible due to heating of machine

• allergies to contrast dyes

• snapshot and not active brain image like in fMRI

reasons to use MRI

the safer option because it does not have radiation

(use strengths)

contributions of MRI to psychology

MRIs have made a big impact on neurological disorders such as brain tremors and strokes by providing clear images that help in diagnosis and treatment planning. They have also advanced our understanding of brain structure and function in mental health conditions.

localization of function

different parts of the brain have different functions and are related to different behaviors

mid temporal lobe

processing auditory information, language comprehension, and semantic knowledge, as well as playing a role in visual memory

neuroplasticity

the capacity of the brain to mold itself to new conditions like after injury (stroke) or while learning new concepts by creating new synapses which is where the neurons send signals to communicate with each other and send messages to the rest of the body and brain.

grey matter

contains a high density of neuronal bodies (neurons) —> increase in grey matter correlates to increase in neurons and more neural density

neural density

amount of neurons in a given volume

voxel-based morphometry

a neuroimaging technique to analyze MRI scans and determine if there were changes in neural density

neural pruning

the brains ability to “erase” old synapses that are not being used anymore to be able to make new neural connections

neurotransmitters

chemical messengers that carry messages from one neuron to another. There are neurotransmitters that affect specific behaviors

synapse

where neurons connect and communicate with each other —> can be with itself, neighbor neurons, or in other regions of the brain. Where the axon approaches a dendrite and forms a synaptic gap to pass neurotransmitter to dendrite

excitatory

increases the likelihood that neuron will fire an action potential, thereby promoting communications between neurons

inhibitory

decreases the likelihood of neuron firing an action potential (preventing it from going across synapse)

agonist

a substance that enhances or mimics the effect of a neurotransmitter at the synapse, thereby increasing neuronal activity. All neurotransmitters are endogenous agonists

antagonist

binds to receptors and counteracts/blocks the neurotransmitter’s effect

acetylcholine

agonist, excitatory at neuromuscular junction (in the studies looked at) but inhibitory at the heart

functions: muscle control (slows heart rate), learning, and memory (spatial memory)

implicated in alzheimer’s disease

reduced in the hippocampus and neocortex which impacts learning and memory. A neurotransmitter essential for muscle control and cognitive functions, including learning and memory, particularly related to spatial memory.

scopolamine

antagonist of acetylcholine. (blocks the effects of it)

hormones

regulate the human body by delivering messages through the bloodstream and endocrine system that influence various physiological processes, including growth, metabolism, mood, and reproductive functions.

oxytocin

AKA love hormone

identified by Sir Henry H. Dale in 1906

produced in the hypothalamus

stored and released into the blood by the pituitary gland

plays a role in sexual reproduction, childbirth, and social bonding

pheromones

a chemical communication within members of the same species. It is said that they affect behavior but it is not yet proven that they are real.

MHC

believed to help individuals identify potential mates by if they have compatible immune systems, thought to play a role in mate selection

genes in behavior

genes are segments of DNA that they contain instruction for building proteins which control an organism’s development and function, such as behavior

passed down which predispose offspring to similar behaviors as parents

MAOA gene

a gene associated with the regulation of neurotransmitters in the brain. Variants of this gene have been linked to aggressive behavior and impulsivity.

DLX1 gene

known to be involved in the production of neurons in the stress center of the brain which can explain high anxiety and overreaction

genetic similarity —> gene-environment interaction

modern interpretation of behavior that considers how genes and environments influence each other in the development of behavioral traits.

studies on either MZ or DZ twins that use their genetic similarities to help with the examination of environmental influences on behavioral traits.

used to study the influence of genotype on behavior

genetic heritability

the quantitative measure of the relative contribution of genetic factors into a trait or behavior.

Epigenetics

regulation of gene expression that result in the deviation of phenotype

can be attributed to environmental influences and how the environment influences genes

within this there are methyl or acetyl markers that are added to DNA that can affect gene activity.

falconer model

phenotype is comprised of three different parts —> genetics, environment (shared and individual)

mathematic model

twin-kinship studies

studies on either MZ or DZ twins that use their genetic similarities to help examine environmental influences on behavioral traits

influence of genotype on behavior

strengths: MZ = 100% same genotype which removes all confounding variable

weaknesses: not highly replicable, not generalizable

evolutionary explanation

attempt to explain behavior through the lens of the theory of evolution which explains behavior from a primal point of view

theory of evolution

a combination of darwin’s theory with the discoveries of genetics

sexual selection

A form of natural selection where individuals with certain traits have a higher reproductive success than others due to their ability to attract and/or mate with more individuals

intrasexual: competition between one sex (usually males) for access to mates. strongest passes on genes typically

intersexual: members of one sex will choose someone from the other sex for characteristics (social status/attractiveness)

survival of the fittest

the organism with the better suited traits for environment will survive and pass down their traits

natural selection

selected members who are better suited for the environment will be more likely to breed and thus more likely to pass on traits

parental investment theory

the sex that is required to invest more in offspring are more choosy in picking mates

evolution

process by which organisms change from one generation to the next as a result in change of heritable traits

relationship between brain and behavior

refers to how brain activity and structures influence actions, thoughts, and emotions in individuals.

study: Draganski (2004)

research method: experiment

ethical considerations: informed consent and protection from harm

hormones and pheromones and their effects on behavior

study: scheele

research method: experiment

ethical considerations: protection from harm and deception

relationship between genetics and behavior

refers to how genetic factors influence individual behavioral patterns and predispositions, including traits like aggression, intelligence, and mental health.

study: Kaminski (2008)

research method: observations, interviews

ethical considerations: informed consent and confidentiality

Draganski 2004

techniques, neuroplasticity, localization

juggling

Maguire 2000

techniques, neuroplasticity, localization

taxi drivers

Antanova

neurotransmitters

fMRI Arena task

Piccart and d’Hooge

neurotransmitters

maze with rats

Scheele

hormones

stop-distance and approach/avoidance task (infedility)

kosfeld

hormones

investors game (trust)

Wedekind

evolutionary explanation, pheromones

smelly t-shirt study (MHC)

Zhou

pheromones

stick figures (AND and EST)

Kaminski

genes, genetic similarity

twin study - law twin/war twin

Weder

genes

MAOA with children

Brunner

genes

family study - dutch males

TJ Bouchard

genetic similarity

reared apart twins and they all took tests

Buss

evolutionary explanation

ranking and mate selection