EoY [SAQ] Bio/Cog Flashcards
Describe how to structure an SAQ
- Define
- Explain/study
- Considered judgement
You will be asked to outline (give an overview of), describe (give a detailed description) or explain (give reasoning for why) a topic area within that approach.
[Bio] Techniques
MRIs:
- Magnetic Resonance Imaging
- Can be used to examine almost any part of the body
- Frequent use: detect changes in blood flow and oxygen levels that result from the brain’s activity
- Make use of strong magnetic fields, magnetic field gradients, and radio waves to create images of the brain and other organs
P: non-invasive, excellent resolution, is practical, is safe, allows for individuals to be tested repeatedly [1–2 minutes]
Maguire et al. 2000
AIM: See whether the brains of london taxi drivers would be somehow different as a result of exceptional training they have to do to be certified
PROCEDURE:
- 16 right-handed male london taxi drivers brains were MRI scanned [‘the knowledge’ & have licenses for at least 1.5 years]
- Compared w/ MRI scans of - 50 right-handed males who don’t drive taxis (control)
- Controls taken from MRI database
- Study is correlational
- Double-blind study
FINDINGS:
- Posterior hippocampi of taxi drivers were significantly larger than control
- Anterior hippocampi significantly smaller
- Volume of right posterior hippocampi correlated w/ amount of the time spent as a taxi driver
- No other differences observed in other parts of the brain
- Maguire argues that this demonstrates that the hippocampus may change in response to environment and demands
Connection: MRIs suited for use in correlational studies in which movement is not required. Allow good observation of volume and activity differences.
[Bio] Localization
Localization:
- cognitive process is the result of distributive processing [areas coming together] -> many areas are specialized
- connectome -> map of neural connections
Hippocampus ->
- part of the limbic system [consolidation of information from short-term -> long-term memory, spatial memory (navigation)]
Limbic system: (emotional brain) major focus of psychological research for it’s role in memory & emotion
Amygdala: plays role in formation of emotional memory & fear responses
Maguire et al. 2000
AIM: See whether the brains of london taxi drivers would be somehow different as a result of exceptional training they have to do to be certified
PROCEDURE:
- 16 right-handed male london taxi drivers
brains were MRI scanned & compared w/ MRI scans of - 50 right-handed males who don’t drive taxis (control)
In order to take part in study, P. had to complete ‘the knowledge’ & have licenses for at least 1.5 years
- Controls taken from MRI database
Included range of ages so that age wasn’t confounding variable
- Study is correlational
- IV is not manipulated, but is naturally occuring
- R. looking to see if there was a relationship between no. of years driving a taxi & anatomy of one’s brain
double-blind study - researcher did not know whether they were looking at a taxi scan or control
FINDINGS:
- Posterior hippocampi of taxi drivers were significantly larger than control
- Anterior hippocampi significantly smaller
- Volume of right posterior hippocampi correlated w/ amount of the time spent as a taxi driver
- No other differences observed in other parts of the brain
- Maguire argues that this demonstrates that the hippocampus may change in response to environment and demands
EVALUATION:
- Double-blind; no researcher bias
- Age is not a confounding variable
- Can it be generalized to women?
??[Bio] Neuroplasticity
Def. The ability of the brain to form and reorganize synaptic connections, especially in response to learning , experience, or following injury.
Neurons:
- Neurons can extend their connections but new ones cannot be grown
- Brain never stops changing
- Fixed number of brain cells but not connections (2,500 synapses at birth - 6 times as many when you are 3 - half when you are an adult) -> neural pruning
- Old connections are reinforced for short term / reinforced learning
Plasticity:
- dendritic branching -> dendrites of the neurons grow in numbers and connect with other neurons [repeated fiering]
- long-term potentiation -> longer periods of depolarization
- neural arborization -> protein synthesis and gene expression
- synaptic pruning -> brain removes synapses that are no longer needed
Maguire et al. 2000
AIM: See whether the brains of london taxi drivers would be somehow different as a result of exceptional training they have to do to be certified
PROCEDURE:
- 16 right-handed male london taxi drivers
brains were MRI scanned & compared w/ MRI scans of - 50 right-handed males who don’t drive taxis (control)
In order to take part in study, P. had to complete ‘the knowledge’ & have licenses for at least 1.5 years
- Controls taken from MRI database
Included range of ages so that age wasn’t confounding variable
- Study is correlational
- IV is not manipulated, but is naturally occuring
- R. looking to see if there was a relationship between no. of years driving a taxi & anatomy of one’s brain
double-blind study - researcher did not know whether they were looking at a taxi scan or control
FINDINGS:
- Posterior hippocampi of taxi drivers were significantly larger than control
- Anterior hippocampi significantly smaller
- Volume of right posterior hippocampi correlated w/ amount of the time spent as a taxi driver
- No other differences observed in other parts of the brain
- Maguire argues that this demonstrates that the hippocampus may change in response to environment and demands
EVALUATION:
- Double-blind; no researcher bias
- Age is not a confounding variable
- Can it be generalized to women?
[Bio] Neurotransmission
Agonists:
- Binds to receptors to activate them (enhance effect)
- Dopamine agonist will bind to receptors ( on the dendrites of the next neuron) to activate them
- Increases strength of a neurons signal
- Increases the likelihood that a signal goes through
- Can act like different neurotransmitters that have similar functions (chemical structures)
- Some drugs can act as agonists for serotonin or dopamine
- Agonists are typically not found in the body (medication)
Antagonists:
- Block receptors
- Lead to a weaker signal or none at all (reduce likelihood for a signal to be transmitted)
Process:
Step 1: An action potential arrives at the axon terminal
Step 2: Membrane depolarization from action potential causes influx of calcium ions
Step 3: Docking of synaptic vesicles at the membrane
Step 4: Release of neurotransmitters into the synapse
Step 5: Receptor Activation
Step 6: Postsynaptic potentials generated in postsynaptic cell summate
Step 7: Neurotransmitter Inactivation [ex.reuptake]
Rogers and Kesner 2003
AIM: Investigate the role of acetylcholine on the formation and retrieval of memory
PROCEDURE:
- 30 rats trained to learn a simple maze, but before memory was transferred into LTM, rats put into three groups
G1: injected with scopolamine, intended to block the reception of acetylcholine - a neurotransmitter - this was the the no acetylcholine condition
G2: injected with physostigmine, blocking cholinesterase, a drug which “cleans up” acetylcholine from receptor proteins, allowing the acetylcholine to continue to act. This was the high acetylcholine condition
G3: injected with an inert saline solution - this was the control group
- Rats then placed back into the maze and ran multiple trials over two days, learning and memory was measured by comparing the amount of mistakes made while completeing the maze
- First five and last five trials on day 1 taken as a measure of encoding, while the last five trials one day 1 and first five trials on day 2 were taken as a measure of retrieval
RESULTS:
- The no-acetylcholine group showed a deficit in encoding, but not retrieval, making more mistakes during the last five trials of day 1
- High-acetylcholine showed no deficit in encoding - made fewer mistakes during the last five trials on day 1 - but showed a deficit in retrieval
→ acetylcholine plays an important role in memory encoding, however too much acetylcholine may interfere with memory retrieval
EVALUATION:
- Results may not be wholly applicable
- Effects are difficult to isolate [alteration of a neurotransmitter may influence changes in other neurotransmitters too]
- Results indicate that drugs such as physostigmine may be applicable in the treatment of memory disorders
- Rigorously controlled experiment w/ control to avoid confounding variables
- Able to establish cause-and-effect relationships
- Overly reductionist understanding of memory
There are several types of mem. & the process of mem. consolidation is v. complex
[Bio] Hormones
Hormones:
- Class of chemicals that affect behavior
- secreted by glands in the endocrine system -> go into the blood stream to affect target cells
- Take longer, produce long-lasting effects
Adrenalin [Epipherin]:
- Part of the hypothalamic-pituitary-adrenal axis [HPA] when a stimulus threatens us -> hypothalamus responds by activating the pituitary gland
- The pituitary gland then releases a hormone that activates the adrenal glands, which are located on top of your kidneys
- Adrenaline is released into the bloodstream
- Adrenaline causes your blood vessels to send more blood to your brain and muscles, increases your blood pressure, makes your brain more alert, and raises blood sugar levels to give you energy
- Many hormones play more than one role [ex. adrenaline: fight and flight, memory]
Cahill & McGaugh 1995
AIM: Investigate role of adrenaline & amygdala on memory
PROCEDURE:
- P. divided into 2 groups
- Each group saw 12 slides each accompanied with a very different story
1st condition: rather boring story about a woman & her son paying a visit to the father in a hospital where they witnessed a disaster preparation drill of a simulated accident victim
2nd condition: story where boy was involved in a car accident where the feet were severed → quickly brought to hospital where limbs were reattached.
- Stayed in the hospital for weeks & returned home with his mother
- 2 weeks after participating, P. asked to come back - memories of specific detailes were tested
- Recognition task consisting of series of questions about slides with 3 answers to choose from
FOLLOW UP STUDY
- P. in ‘traumatic story’ condition injected with beta-blocker propranolol
- Interferes w/ release of adrenaline→ prevent activation of amygdala to prevent formation of emotional memory
FINAL FINDINGS
Original version: P. w/ more emotionally arousing story demonstrated a better recall of specific story details & slide details
Follow up: 2nd group was no better than the 1st
→ adrenaline & activation of the amygdala play a significant role in the creation of memory linked to emotional arousal
EVALUATION
- Cause-and-effect relationship can be established as adrenaline was blocked in the follow-up
- Lack of ecological validity: study is artificial in nature & highly controlled
- Easily replicated
- Standardized procedure allows other research to test reliability
- Demonstrates internal validity
- Significant difference between total recall of P. in both conditions
[Bio] Pheromones
Def. a chemical substance that is usually produced by an animal and serves especially as a stimulus to other individuals of the same species for one or more behavioral responses
Note: Proven in animals but not humans
- Primer pheromones: Cause slow, long-term physiological changes [ex.hormonal effects] -> more human evidence
- Signaling pheromones : produce rapid behavioral effects [ex. mating]
- Two potential human hormones: Androstadienone (AND) [male semen and sweat], Estratetraenol (EST) [female urin]
- vomeronasal organ -> tube at the base of the nasal cavity [behind nostrils] filled with sensory neurons [found in: amphibians, reptiles, and nonprimate mammals, absents in: birds, primates]
Zhou 2014
AIM: To look at how androstadienone [a steroid] may play a role in human sexual behavior.
PROCEDURE:
- Zhou et al conducted an experiment to investigate the effects of AND and EST on heterosexual and homosexual men and women.
- The sample included four groups of healthy non-smokers:
- 24 heterosexual males
- 24 heterosexual females
- 24 homosexual males
- 24 bisexual or homosexual females
- Participants performed a point-light walker task (PLW) involving a set of moving dots representing human motion.
- Participants identified the sex of the stick figure in motion.
- The task was performed at a similar time each day over three consecutive days.
- Participants were exposed to:
- Androstadienone (AND) mixed with cloves
- Estratetraenol (EST) mixed with cloves
- A control solution mixed with cloves
- Each day, participants only carried out the task while smelling one of the solutions.
- Scents were counterbalanced to control for order effects.
RESULTS:
- Heterosexual females and gay males identified the stick figure as “masculine” more frequently when exposed to AND compared to the control group.
- AND had no significant effect on heterosexual men or lesbian women.
- Smelling EST led heterosexual males to perceive the walkers as more feminine.
- The effect of EST was not statistically significant in bisexual and lesbian women.
- The study suggests AND and EST may influence human sexual behavior.
EVALUATION:
The experiment allowed researchers to establish a cause-and-effect relationship between the independent variable (IV) (AND or EST exposure) and the dependent variable (DV) (rating of the stick figure).
Different findings were obtained for different groups based on gender and sexuality, indicating these variables also influence the strength of the IV’s effect on the DV.
The study was counterbalanced to control for order effects, such as the practice effect.
Hare et al (2017) failed to replicate the study, questioning the reliability of the results.
The dose of AND and EST used was significantly higher than what humans naturally secrete, suggesting the findings may not accurately represent actual human behavior.
[Bio] Ethics
Ethics:
- Future applications of genetic predispositions [discrimination]
- Subject stress or self fulfilling prophecy
- CARDUD:
C - consent
A - anonymity
R - right to withdraw
D - deception
U - under stress or harm
D - debriefing
Caspi et. al. 2003
AIM: see if not only gene had effect on aggression in children as they developed
- Whether environmental stressors may interact w/ gene to determine behaviour
- Interested in gene-environment interaction and which is important to epigenetics
PROCEDURES:
- 26-year study of 1037 children (442 boys)
- Born Dunedin NZ
- Looked at genotype of boys (particularly gene that controls production of MAOA)
FINDINGS:
- By age 11, 36% of children had been maltreated
- Rejection by mother, physical and/or sexual abuse
- Abused + MAOA gene -> more likely to bully others & engage in aggressive, anti-social behaviour [85% as adults]
- Boys who were abused which didn’t have gene did not show any more aggression than boys who weren’t abused
→ supports theory of genetic influence in aggressive behaviour
[Bio] Genes / Behavior
Genes:
- Genes and their DNA are passed down from parents to their offspring [50% per parent]
- Humans have 23 pairs of chromosomes [20,000 – 25,000 genes -> Human Genome Project 1990-2004]
- The environment affects the expression of genes
5-HTT:
- Protein [seratonin transporter]
- A chemical that carries messages between nerve cells in the brain and throughout your body [plays a key role in mood, sleep, digestion]
Caspi et. al. 2003
AIM: Determine possible role of 5-HTT gene in depression after experience of stressful events
PROCEDURE:
- 897 New Zealand 26 year-olds
- Prospective, longitudinal study
- Members of a cohort that had been assessed for mental health on an every-other-year basis until 21
- Divided into groups based on 5-HTT alleles
- G1: 2 short alleles
- G2: 1 short, 1 long allele
- G3: 2 long alleles
- Mutation of 5-HTT gene has shorter alleles
- Asked to fill in ‘stressful life events’ questionnaire
- Asked about frequency of 14 events, s.a. Financial, employment, health & relationship stressors between ages of 21-26
FINDINGS:
- P. w/ one + short version of the allele demonstrated more symptoms t=of MDD & suicidal ideation in response to stressful life events
- Simply inheriting wasn’t enough to lead to depression
- Effect strongest for those with 3+ stressful events
- Gene interacting w/ stressful life events increased likelihood of developing depression
[Bio] Research Method
Correlational studies: investigates relationships between two variables (or more) without the researcher controlling or manipulating any of them
P ->
- Can be used to study variables you are unable to manipulate
- Can indicate where more detailed experiments should be done
C ->
- Correlation does not mean causation
Maguire et al. 2000
AIM: See whether the brains of london taxi drivers would be somehow different as a result of exceptional training they have to do to be certified
PROCEDURE:
- 16 right-handed male london taxi drivers
brains were MRI scanned & compared w/ MRI scans of - 50 right-handed males who don’t drive taxis (control)
In order to take part in study, P. had to complete ‘the knowledge’ & have licenses for at least 1.5 years
- Controls taken from MRI database
Included range of ages so that age wasn’t confounding variable
- Study is correlational
- IV is not manipulated, but is naturally occuring
- R. looking to see if there was a relationship between no. of years driving a taxi & anatomy of one’s brain
double-blind study - researcher did not know whether they were looking at a taxi scan or control
FINDINGS:
- Posterior hippocampi of taxi drivers were significantly larger than control
- Anterior hippocampi significantly smaller
- Volume of right posterior hippocampi correlated w/ amount of the time spent as a taxi driver
- No other differences observed in other parts of the brain
- Maguire argues that this demonstrates that the hippocampus may change in response to environment and demands
EVALUATION:
- Double-blind; no researcher bias
- Age is not a confounding variable
- Can it be generalized to women?
[Cog] Memory Model
Memory Models:
- memory refers to the process by which information is encoded, stored, and retrieved
- model of memory is a hypothesized representation of memory
- models change over time as new evidence becomes available
Multistore memory model -> Atkinson and Shiffrin
- inspired by computer science
- sensory register, short-term, and long-term store
- flow between three permanent storage systems of memory
- Assumptions: memory consists of a number of separate locations in which information is stored, memory processes are sequential, each memory store operates in a single, uniform way
- Milners Magic Number
Milner 1966
CASE STUDY:
- Example of biological evidence that STM and LTM are located in a different store in the brain
- HM had anterograde amnesia
- Could not transfer new information into LTM - but still had access to many of his memories prior to his surgery
- Fact that he could create new procedural memories shows that mem. may be more complex than the M-SMM predicts
EVALUATION OF MULTI-STORE MEMORY MODEL
STRENGTHS:
- Significant supporting research (both cognitive and biological case studies of patients w/ brain damage)
- Model’s historical importance - gave psychologists a way to talk about memory & much of the research which followed was based on the model
LIMITATIONS:
- Over-simplified: assumes that each store works as an individual unit
- Does not explain memory distortion
- Does not explain why some things may be learnt w/ minimal rehearsal
- Or why sometimes it is repeatedly rehearsed but not transferred to LTM
[Cog] Emotion
Flashbulb memory def. a highly detailed, exceptionally vivid “snapshot” of the moment when a surprising and emotionally arousing event happened
Importance-driven model -> This model emphasizes that personal consequences determine intensity of emotional reactions.
- special-mechanism hypothesis -> existence of special biological memory mechanism that, when triggered by an event exceeding critical levels of surprise, creates a permanent record of the event [implies that flashbulb memories have different characteristics than “ordinary memories.”]
Sharot 2007
AIM: Determine potential role of biological factors in the FBM
PROCEDURE:
- 3 years after 9/11
- 24 P. in New York during 9/11
- Brain activity observed using functional magnetic resonance imaging (fMRI)
- Presented word cues: including ‘summer’ or ‘september’ to link events of their summer or 9/11 with the other word
- Brain activity recorded
- After fMRI P. rated memories for vividness, detail, confidence & arousal & asked to write personal memories
FINDINGS:
- Only ½ of participants reported having Flashbulb memories
- This ½ was also closer to World Trade Center at the time of event
- Included more specific details
- Activation of amygdala was higher when recalling memories of the terrorist attack for P. closer to the event
- P. further away had equal levels of response for events of preceding summer & attack
- Strength of amygdala activation correlated w/ FBM
- Suggests close personal experience may be critical in engaging neural mechanisms which produce vivid memories s.a. those of FBMT
EVALUATION:
- Does not explain why someone who simply saw it on - TV may claim to have a FBM
- Correlational: does not establish a cause and effect relationship w/ memory attribution in the amygdala
[Cog] Ethics
Ethical concerns:
- Who gave consent
- If he continues to forget is he also giving continuous consent
- Results of the surgery were unclear before it was performed
- CARDUD
Milner 1966
CASE STUDY:
- Example of biological evidence that STM and LTM are located in a different store in the brain
- HM had anterograde amnesia
- Could not transfer new information into LTM - but still had access to many of his memories prior to his surgery
- Fact that he could create new procedural memories shows that mem. may be more complex than the M-SMM predicts
EVALUATION OF MULTI-STORE MEMORY MODEL
STRENGTHS:
- Significant supporting research (both cognitive and biological case studies of patients w/ brain damage)
- Model’s historical importance - gave psychologists a way to talk about memory & much of the research which followed was based on the model
LIMITATIONS:
- Over-simplified: assumes that each store works as an individual unit
- Does not explain memory distortion
- Does not explain why some things may be learnt w/ minimal rehearsal
- Or why sometimes it is repeatedly rehearsed but not transferred to LTM
[Cog] Research Method
Case Studies: Observing one person for an extended period of time [often uses method triangulation].
Pros ->
- Inexpensive
- Can be done remotely
- Provide insights into rare conditions
Cons ->
- Can take longer to analyze
- Can be inefficient
Milner 1966
CASE STUDY:
- Example of biological evidence that STM and LTM are located in a different store in the brain
- HM had anterograde amnesia
- Could not transfer new information into LTM - but still had access to many of his memories prior to his surgery
- Fact that he could create new procedural memories shows that mem. may be more complex than the M-SMM predicts
EVALUATION OF MULTI-STORE MEMORY MODEL
STRENGTHS:
- Significant supporting research (both cognitive and biological case studies of patients w/ brain damage)
- Model’s historical importance - gave psychologists a way to talk about memory & much of the research which followed was based on the model
LIMITATIONS:
- Over-simplified: assumes that each store works as an individual unit
- Does not explain memory distortion
- Does not explain why some things may be learnt w/ minimal rehearsal
- Or why sometimes it is repeatedly rehearsed but not transferred to LTM
[Bio] Evolution
Evolution:
- Darwins theory of natural selection -> explains how species acquire adaptive characteristics to survive in an ever-changing environment
- Galapagos Islands -> Finches on different islands had different types of beaks [food availability]
- Evolutionary psychologists -> attempt to explain how certain human behaviors are the result of the development of our species over time [natural selection cannot select for a behavior only genes]
- Assumption by evolutionary psychologists that behavior is based on genetics
Wedekind 1995
AIM: Investigate influence of MHC genes on mate selection in females
PROCEDURE:
- Quasi-experimental study, 49 females and 44 males
- Female P. asked to report if using oral contraceptives, given nose spray to ensure nasal health, given a book to sensitize smell perception
- Male P. asked to wear shirt for two nights in a row, keep the shirt in a plastic bag between nights, given scentless soap & detergent to ensure natural smell, asked not to partake in activities which may alter their scent, i.e. smoke, drink alcohol, engage in sexual activities etc.
- When Female P. in second week after menstruation (when most sensitive to odor) P. were asked to rate odor of 7 shirts on intensity, sexiness and pleasantness
- 3 male P. with similar MHC genes, 3 with dissimilar - MHC genes and 1 (unworn) control shirt
- Shirts placed in a cardboard box → double blind study
FINDINGS:
- Female P. not on oral contraceptives rated dissimilar - MHC higher on pleasantness, vice versa for P. on oral contraceptives
- Odors of MHC-dissimilar men reminded females of current/former mates
→ MHC diversity seems to influence mate selection supporting ToE (inc. survival)
- As oral contraceptives imitate steroids naturally released during pregnancy, P. may prefer partners who can help them take care of the children
EVALUATION:
- Highly replicable
- eAttractiveness =/= mate selection: other factors also play a role - arguably too reductionist, ignoring cognitive and sociocultural factors
