The Brain and Behavior - Biological Approach

Question 1

Methods in Biological Approach

Answer 1

Case Studies

Question 2

Case Studies

Answer 2

Often provide researchers w/ a situation they could never ethically reproduce in a lab
→ often longitudinal to observe both short-term and long-term effects of damage

Question 3

Longitudinal Studies

Answer 3

Correlational research that involves repeated observations of the same variables over long periods of time
→ holistic: range of effects of the damage (rather than one behavior)
Use triangulation: may include interviews w/ family, psychometric testing (IQ/Personality testing), experiments and observations
Triangulation: involves using multiple data sources, multiple researchers or multiple research methods to reach a richer understanding of a behavior/cognitive process

Question 4

limitations in biological approach

Answer 4

Researchers do not manipulate an IV
No cause & effect relationship can be established
Case studies are individual: cannot be generalized to all humans
Cannot be replicated as it naturally occurring
May be difficult to verify info about P. before incident
Info on patients IQ, problem solving skills, memory or interpersonal skills is often reliant on memory of family
Not accurate measure & memory may not be accurate

Question 5

strengths in biological approach

Answer 5

Provide important info to study effects of brain damage over time & spark new research
Psychologists often use similar research to verify findings
May perform research on animals to investigate hypothesized relationship between damage to a specific area of the brain & behavior

Question 6

Techniques in Biological Approach, and why use technology?

Answer 6

MRI, fMRI, PET
because allows reseacher to see localization of function - functions of parts of brain & how they react to behavior

Question 7

MRI

Answer 7

→ HM: Milner 1966; Maguire 1999; Eugene Pauly
Magnetic resonance imaging
Gives 3D picture of brain structure
Used with HM to determine extent of damage
Uses magnetic field & radio waves to map activity of hydrogen molecules present in different brain tissue to different degrees
Can be viewed as slice from any angle or 3D view of the brain

Question 8

advantages of MRI

Answer 8

Non-invasive process: minimal potential of harm
High resolution: gives R. good idea of brain structure

Question 9

limitations of MRI

Answer 9

Only indicates structure
Does not map what is actually happening
Correlational in nature: no clear cause & effect can be established

Question 10

fMRI

Answer 10

functional MRI
→ Baumgartner et al. 2008; Harris & Fiske 2006; Sharot et al. 2006
Shows brain activity & indicates which areas of brain are active when engages in behavior/cognitive processes
Measures changes in blood flaw in active brain
Oxygen level as measurement of neural activity
Active brain uses more oxygen & blood flow increases

Question 11

advantages of fMRI

Answer 11

Higher resolution than PET scans
Easier to carry out
non-invasive : no radio-isotope necessary
Produces a film that demonstrates change in brain activity

Question 12

limitations of fMRI

Answer 12

Non-natural environment for cognition
Lack of ecological validity
P. may experience anxiety due to claustrophobic nature of machine
Artifacts in imaging: brain activity may be related to anxiety/reaction to machine
Artifacts: Something observed in a scientific investigation/experience that is not naturally present but occurs as a result of an investigative process
Use of color may be exaggerated
Much of activity in brain is spontaneous & not a reaction to stimuli
Difficult to know exactly which areas of the brain are active in a behavior
For both MRI and fMRI iron objects must be removed
Sample size may be reduced due to metal implants

Question 13

PET

Answer 13

Positive emission tomography
Observe metabolic processes in brain by detecting gamma rays emitted by a tracer
Based on the assumption that areas of high radioactivity are associated w/ brain activity
P. given safe dose of radioactive tracer compound
Through modified glucose molecules (FDG)
Injected into blood & can enter brain
More glucose needed in active areas, and thus PET detects radioactive tracer
30min-2hrs
Produced multi-colored image of where brain is most active

Question 14

advantages of PET

Answer 14

Allows participants to perform psychological tasks while brain activity is observed

Question 15

limitations of PET

Answer 15

Injection w/ small amount of radioactive material
Not cause harm but is an invasive practice & raises ethical concerns
Slow & poor resolution

Question 16

localization and plasticity

Answer 16

Localization of function describes the theory that specific parts of the brain are responsible for specific behaviors/cognitive processes. HM case study is evidence of this theory - the hippocampus being responsible for transferring short-term memory to long-term.

E.g. memory research. Cognitive processing is argued to be the result of distributive processing rather than localization of function - parts of the brain have to work together to create and retrieve memories.

Question 17

4 key areas of brain

Answer 17

BRAIN STEM: regulating life functions (e.g. breathing, heart rate, and blood pressure)
CEREBELLUM: balance and motor functions including speech production. Additionally in learning (classically conditioned responses)
CEREBRUM: initiates and coordinates movement and regulates temperature
LIMBIC SYSTEM: behavioral and emotional responses

Question 18

4 sections of cerebral cortex

Answer 18

THE FRONTAL LOBE: executive functions (planning, decision-making, and speech)
THE OCCIPITAL LOBE: visual processing
THE PARIETAL LOBE: perception of stimuli
THE TEMPORAL LOBE: auditory processing and memory

Question 19

Study of HM what type of method?

Answer 19

Case Study

Question 20

Study of HM context

Answer 20

WILLIAM SCOVILLE performed experimental surgery: removed tissue from medial temporal lobe (inc. hippocampus) on both side of HM’s brain
After op. HM remembered childhood well & personality was unchanged
HM suffered from anterograde amnesia
No longer able to transfer info from STM to LTM

Question 21

HM Study (info)

Answer 21

localization
AIM: To study the role of the hippocampus on memory formation in a longitudinal case study
PROCEDURE:
Example of method triangulation
Psychometric testing: 12 tests were given, and results were above average
Direct observation of behavior
Interviews w/ HM & family members
Cognitive testing: memory recall & learning tasks (s.a. reverse mirror drawing)
MRI to determine extent of damage done (CORKIN 1997)
FINDINGS:
HM could not acquire new episodic knowledge (memory of events) or new semantic knowledge (general knowledge about the world)
Suggests brain structures removed important for LTM (explicit memory)
Was able to form a cognitive map of the spatial layout of his home
Had capacity for working memory, as he could hold a normal conversation
Procedural memories well maintained
Showed improvements on performance of new skills (s.a. Rev. mirror drawing)
According to MRI scans from 1997 & 2002 (CORKIN) the temporal lobe (inc. hippocampus) had most damage: explains problem of transferral of STM to LTM
→ Researchers conclude Hippocampus plays critical role in converting memory from STM to LTM
Not site of storage of STM or LTM, but plays role in organization & storage of permanent memory elsewhere in brain

Question 22

Brain Plasticity

Answer 22

brain’s ability to alter its own structure between neurons following the changes within the body or in the external environment. High levels of stumulan and learning opportunities lead to an increase in the density of neural connections

Question 23

what type of method was used in MAGUIRE ET AL. (2000)

Answer 23

quasi (case and effect)

Question 24

Maguire et al. (2000)

Answer 24

brain plasticity
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 hippocampus significantly smaller
Volume of right posterior hippocampus 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

Question 25

DRAGANSKI ET AL (2004)

Answer 25

brain plasticity
AIM: Find out whether the human brain can change structure in response to environmental demands
PROCEDURE:
Random sampling design, self-selected sample
Randomly allocated a sample of volunteers into 2 groups
One : jugglers
Two : non-jugglers
Made sure that both groups had no experience of juggling before the start of the experiment
First MRI performed
Participants in the juggler group subsequently spent three months learning a classic juggling routine with three balls
Second MRI performed
Participants in the juggler group spent three months where they were instructed not to practice juggling
Third MRI performed
FINDINGS:
Prior to the start of the experiment there was no difference in brain structure
Second scan the juggler had more gray matter in some areas of the cortex mostly the mid-temporal area
Third scan differences decreased but jugglers denser gray matter
If we practice something then our brain will increase and when we stop practicing then it will decrease again, but often not to its original state

Question 26

Neurotransmitters

Answer 26

Neurons (nerve cells) are a big reason behind behavior. The process by which the messages are sent is called neurotransmission. The electrical impulse traveling along the body of the neuron is called action potential.

Neurotransmitters show to have a variety of effects on behavior. Mood, sleep, learning and memory, sexual arousal, and mental illnesses.

Question 27

what is acetylcholine and what effect does it have?

Answer 27

neurotransmitter - Consideration of memory in hippocampus

Question 28

what is dopamine and what effect does it have?

Answer 28

Control the brain’s reward and pleasure centers. Key role in motivation; low levels are linked to addictive behavior

Question 29

what is serotonin and what effect does it have?

Answer 29

Sleep, arousal levels, and emotion

Question 30

what is Norepinephrine and what effect does it have?

Answer 30

Arousal and alertness

Question 31

inhibitory?

Answer 31

NEUROTRANSMITTERS
Decrease the likelihood of a neuron firing by hyperpolarizing the neuron. E.g. GABA.

Question 32

exhibitory?

Answer 32

NEUROTRANSMITTERS
Increase the likelihood of a neuron firing by depolarizing the neuron. E.g. acetylcholine.

Question 33

ROGERS AND KESNER (2003)

Answer 33

neurotrasmitters
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 completing 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

Question 34

ANTONOVA (2011)

Answer 34

AIM: To look at the importance of acetylcholine in encoding spatial memory in humans
PROCEDURE:
20 healthy male adults partaking in double-blind study
P. injected with either scopolamine - antagonist which blocks acetylcholine receptor sites, decreasing availability of acetylcholine - or a placebo 70-90 min before task
Participants put into fMRI while playing “arena task”
Virtual reality game in which the goal was to navigate a map and reach a pole, P. then had 30 seconds to rehearse the path taken before being dropped at a new starting point. Spatial memory was used to get to the pole
P. trained in the game so they were familiar with rules and controls
After training P.’s brain activity measured for 6 trials
P. returned 3-4 weeks later and redid the task with the opposite treatment of their first trials
FINDINGS:
When P. were injected with scopolamine a significant reduction in the activation of the hippocampus was demonstrated in comparison to the placebo
Scopolamine impairs memorisation of new information by decreasing activity within the hippocampus
→ acetylcholine may play a key role in the encoding of spatial memory in both rats and humans

Question 35

an agonist

Answer 35

produces a response by binding to a receptor on the cell
acetylcholine is an agonist for the ACh receptor site

Question 36

an antagonist

Answer 36

opposes the action by binding to the receptor - doesn’t allow the neurotransmitter to do its job
E.g. scopolamine for ACh

Question 37

what are extrenal agnosits?

Answer 37

exogenous agonists (e.j. drugs)

Question 38

hormones

Answer 38

Secreted by glands in endocrine system
Released directly into bloodstream: take longer to produce changes in behavior
But effects last longer than action potential
Can only produce reaction in target cells: have appropriate cell for hormone
When hormone binds to the target cell it either increases or decreases function
Some hormones ‘act as neurotransmitters’, and work in the brain by targeting receptor sites on neurons synaptic gap even though it’s secreted by endocrine gland.

Question 39

what is adrenaline and what effect does it have?

Answer 39

hormone
Secreted by adrenal glands: responsible for arousal/’fight or flight’ response. Plays role in emotional memory formation.

Question 40

what is cortisol and what effect does it have?

Answer 40

hormone
Secreted by adrenal glands: helps control blood sugar levels, regulates metabolism. Reduces inflammation & assists memory formation.

Question 41

what is melatonin and what effect does it have?

Answer 41

hormone
Secreted by pineal gland: signals relaxation & lowers body temperature, which help with restful sleep.

Question 42

what is neuropeptide Y and what effect does it have?

Answer 42

hormone
Produced by hypothalamus: acts as neurotransmitter in the brain. Stimulates: food intake, reduces anxiety & stress, reduces pain perception, affects circadian rhythm. Higher levels of NPY are linked to higher levels of resilience.

Question 43

what is oxytocin and what effect does it have?

Answer 43

hormone
Produced by hypothalamus & secreted by pituitary gland: acts as a neurotransmitter when affecting the brain. Plays role in mother-child attachment, possibly in social bonding & trust between people

Question 44

what is tetosterone and what effect does it have?

Answer 44

Produced by testes: plays role in aggressive behavior → does not cause aggression but higher levels of testosterone leads to higher levels of aggression

Question 45

pheremones?

Answer 45

a chemical substance that is produced and released by an animal which affects the behavior/physiology of others of their species. However, it’s not clear whether this is also true in humans.

Question 46

2 types of pheremones in animals?

Answer 46

primer pheromones
signaling pheromones

Question 47

primer pheromones

Answer 47

slow, long-term physiological changes (hormonal effects)

Question 48

signaling pheromones

Answer 48

rapid behavioral changes effects (mating)

Question 49

2 potential human pheromones

Answer 49

anderostadienone (AND)
estratetraenol (EST)

Question 50

anderostandienone (AND)

Answer 50

male semen and sweat

Question 51

estratetraenol (EST)

Answer 51

female urine

Question 52

wedekind (1995)

Answer 52

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