Biological Flashcards
Explain localisation of behaviour, with reference to one study.
LOCALISATION: The idea that different parts it the brain are responsible for different behaviours.
- eg, hippocampus is responsible for memory and the basal ganglia is responsible for movement and reward systems.
HM MILNER:
AIM: To study the role of the hippocampus in memory formation.
METHOD: METHODICAL TRIANGULATION
PROCEDURE: removed parts or temporal lobe in HM’s memory.
- psychometric testing
- direct observations on behaviour
- cognitive testing ( memory recall)
FINDINGS: lost the ability to form new memory.
-formed cognitive map of spatial layout of his house.
- procedural memories were maintained.
- hippocampus had most damage ( retrieved using MRI)
CONCLUSION: hippocampus plays a role in declarative memory but jot procedural memory.
Explain one technique used to study the brain in relation to behaviour with reference to one study.
MRI SCANNING (magnetic resonance imaging):
-enables images of the brain structure to be taken in order to look at behaviour.
-two powerful magnets produce a strong magnetic field which forces protons to align in the body.
- when radio waves are pulsed through the body, the protons are stimulated and strain against the pull of the magnetic field.
MAGUIRE (2000)
AIM: to examine whether structural changes could be detected to the brain if people with extensive experience of spacial navigation.
METHOD: Structural MRI scan.
PROCEDURE:
- Structural MRI scans were obtained from 16 right handed male london taxi drivers who had drove for more then 1.5 years.
- same scans taken of 50 males ( non taxi drivers ) ( this was included to compare the groups).
FINDINGS:
- Increased grey matter was found in the posterior hippocampus of the taxi drivers.
-non drivers hippocampi were smaller.
-the volume of the right posterior hippocampi correlated with amount of time spent as a taxi driver.
CONCLUSION:
- anterial hippocampus region is involved during encoding of new environmental layouts.
- posterior hippocampus involved with previous learned spacial information.
Explain neuroplasticity, with reference to one study.
-BRAIN PLASTICITY refers to the brains ability to rearrange the connections between its neurons.
-High levels of stimulation and numerous learning opportunities leads to increase in density neurons.
-DENDRITIC BRANCHING
Neurone create a new trace in the brain and connect with others.
ARBORISATION- growth of dendritic spines.
MAGUIRE (2000)
AIM: to examine whether structural changes could be detected to the brain if people with extensive experience of spacial navigation.
METHOD: Structural MRI scan.
PROCEDURE:
- Structural MRI scans were obtained from 16 right handed male london taxi drivers who had drove for more then 1.5 years.
- same scans taken of 50 males ( non taxi drivers ) ( this was included to compare the groups).
FINDINGS:
- Increased grey matter was found in the posterior hippocampus of the taxi drivers.
-non drivers hippocampi were smaller.
-the volume of the right posterior hippocampi correlated with amount of time spent as a taxi driver.
CONCLUSION:
- anterial hippocampus region is involved during encoding of new environmental layouts.
- posterior hippocampus involved with previous learned spacial information.
Explain the effect of one neurotransmitter on human behaviour, with reference to one study.
Neurotransmitter = chemical signals released from presynaptic nerve terminals into the synaptic cleft
(chemical messengers that makes communication between neurons in the brain and nervous system
Acetylcholine is a neurotransmitter that plays a role in memory, learning, attention, arousal and involuntary muscle movement. Medical conditions associated with low acetylcholine levels include Alzheimer’s disease and myasthenia gravis
impulsive aggression = by low cerebrospinal fluid levels of serotonin.
Rogers and Kesner:
AIM = to determine the role of acetylcholine in the formation of spatial memory
PROCEDURE = 30 rats got familiar with a Hebb Williams maze by placing food in one corner.
Two conditions:
- Experimental - injected with scopolamine, intended to block the receptor sites of acetylcholine, thus, inhibiting response before running the maze
Control - placebo saline solution
injections straight into hippocampus
Encoding of memory - the average number of errors made on the first five trials of Day 1 compared to the last five trials of Day 1,
Retrieval - the average number of errors made on the first five trials of Day 2 compared to the last five trials of Day 1.
Results:
- Scopolamine group took longer and made more mistakes in the learning of the maze - that is, there was a higher average number of mistakes made on the last five trials on Day 1
- However, it did not appear to have an effect on retrieval of memories that had already been created. It appears that acetylcholine may play an important role in the consolidation of spatial memories
Explain the role of one antagonist with reference to one study.
Antagonists - sit on the receptor sites on the postsynaptic neuron and block the neuron from creating an action potential and subsequently block the neurotransmitters from firing their message to the next neuron. (e.g. scopolamine) + antipsychotics
inhibits or opposes agonists. Blocks activity of agonist. Reverses.
Agonist = An agonist is a substance that mimics the actions of a neurotransmitter or hormone to produce a response when it binds to a specific receptor in the brain.
Natural or artificial
Scopolamine = medication used to manage and treat postoperative nausea and vomiting and motion sickness.
Rogers and Kesner:
AIM = to determine the role of acetylcholine in the formation of spatial memory
PROCEDURE = 30 rats got familiar with a Hebb Williams maze by placing food in one corner.
Two conditions:
- Experimental - injected with scopolamine, intended to block the receptor sites of acetylcholine, thus, inhibiting response before running the maze
Control - placebo saline solution
injections straight into hippocampus
Encoding of memory - the average number of errors made on the first five trials of Day 1 compared to the last five trials of Day 1,
Retrieval - the average number of errors made on the first five trials of Day 2 compared to the last five trials of Day 1.
Results:
- Scopolamine group took longer and made more mistakes in the learning of the maze - that is, there was a higher average number of mistakes made on the last five trials on Day 1
- However, it did not appear to have an effect on retrieval of memories that had already been created. It appears that acetylcholine may play an important role in the consolidation of spatial memories
Explain the formation of neural networks with the use of one study.
neural network = a method in AI that teaches computers to process data in a way that is inspired by the human brain.
Neural networks are intricate networks of interconnected nodes, or neurons, that collaborate to tackle complicated problems.
BRAIN PLASTICITY refers to the brains ability to rearrange the connections between its neurons.
-High levels of stimulation and numerous learning opportunities leads to increase in density neurons.
-DENDRITIC BRANCHING
Neurone create a new trace in the brain and connect with others.
ARBORISATION- growth of dendritic spines.
MAGUIRE (2000)
AIM: to examine whether structural changes could be detected to the brain if people with extensive experience of spacial navigation.
METHOD: Structural MRI scan.
PROCEDURE:
- Structural MRI scans were obtained from 16 right handed male london taxi drivers who had drove for more then 1.5 years.
- same scans taken of 50 males ( non taxi drivers ) ( this was included to compare the groups).
FINDINGS:
- Increased grey matter was found in the posterior hippocampus of the taxi drivers.
-non drivers hippocampi were smaller.
-the volume of the right posterior hippocampi correlated with amount of time spent as a taxi driver.
CONCLUSION:
- anterial hippocampus region is involved during encoding of new environmental layouts.
- posterior hippocampus involved with previous learned spacial information.
Explain neural pruning with reference to one study.
Neural pruning = Synaptic pruning, or neural pruning, is the removal of redundant or otherwise unnecessary synaptic connections
a process of removing neurons which may have become damaged or degraded in order to further improve the “networking” capacity of a particular area of the brain.
MAGUIRE (2000)
AIM: to examine whether structural changes could be detected to the brain if people with extensive experience of spacial navigation.
METHOD: Structural MRI scan.
PROCEDURE:
- Structural MRI scans were obtained from 16 right handed male london taxi drivers who had drove for more then 1.5 years.
- same scans taken of 50 males ( non taxi drivers ) ( this was included to compare the groups).
FINDINGS:
- Increased grey matter was found in the posterior hippocampus of the taxi drivers.
-non drivers hippocampi were smaller.
-the volume of the right posterior hippocampi correlated with amount of time spent as a taxi driver.
CONCLUSION:
- anterial hippocampus region is involved during encoding of new environmental layouts.
- posterior hippocampus involved with previous learned spacial information
Explain the role of one agonist with reference to one study.
Agonist = An agonist is a substance that mimics the actions of a neurotransmitter or hormone to produce a response when it binds to a specific receptor in the brain.
Natural or artificial
Neurotransmitters are endogenous agonists - the brain’s natural chemicals that bind to receptor sites, leading to an action potential.
Drugs can play the same role and are called exogenous agonists.
One example of an exogenous agonist is alcohol. Alcohol binds with dopamine receptor sites, causing dopamine neurons to fire. The firing of these neurons results in the activation of the brain’s reward system - the Basal Ganglia, more specifically, the Nucleus Accumbens.
A study conducted by Leyton (2013) investigated the role of alcohol as an exogenous agonist in 26 healthy social drinkers.
LEYTON:
AIM = to investigate effects of alcohol consumption on the dopamine reward system
METHOD =
-Independent sample experiment using a survey and PET Scan.
-Each participant underwent a PET scan after drinking either juice and then later, alcohol. In each condition, they were asked to drink three drinks in 15 minutes.
-The researcher had to categorize the drinkers based on their risk for alcoholism based on personality traits and having a lower intoxication response to alcohol
PROCEDURE = Random assignment to either G1: they consume 3 alcoholic drinks in 15 minutes or G2: consume 3 juice drinks in 15 minutes – All participants take a survey before about drug and alcohol consumption of last year.
Results = Those with high tolerance, who were given alcohol had a large dopamine response in the Basal Ganglia, more specifically, the nucleus accumbens which is responsible for the production of dopamine.
CONCLUSION = Participants with low alcohol response experienced a large amount of dopamine when they took a drink. In contrast, participants with high alcohol response received minimal dopamine response
Explain the role of inhibitory or excitatory synapses in one behaviour with reference to one study.
acetylcholine (exitatory) = neurotransmitter that plays a role in memory, learning, attention, arousal and involuntary muscle movement.
Excitatory synapse = an action potential in a presynaptic neuron increases the probability of an action potential occurring in a postsynaptic cell. INCREASE activity of the receiving neuron
Inhibitory = signals sent across inhibitory synapses REDUCE neuron activity
Rogers and Kesner:
AIM = to determine the role of acetylcholine in the formation of spatial memory
PROCEDURE = 30 rats got familiar with a Hebb Williams maze by placing food in one corner.
Two conditions:
- Experimental - injected with scopolamine, intended to block the receptor sites of acetylcholine, thus, inhibiting response before running the maze
Control - placebo saline solution
injections straight into hippocampus
Encoding of memory - the average number of errors made on the first five trials of Day 1 compared to the last five trials of Day 1,
Retrieval - the average number of errors made on the first five trials of Day 2 compared to the last five trials of Day 1.
Results:
- Scopolamine group took longer and made more mistakes in the learning of the maze - that is, there was a higher average number of mistakes made on the last five trials on Day 1
- However, it did not appear to have an effect on retrieval of memories that had already been created. It appears that acetylcholine may play an important role in the consolidation of spatial memories
Explain the effect of one hormone on human behaviour with reference to one study.
CORTISOL:
-a primary hormone which is released during stress and can impact memory.
- This increases blood sugar in the bloodstream and enhances the brain use of glucose which repair tissue.
NEWCOMER ET AL:
Aim: investigate whether high levels of cortisol interfere with verbal declarative memory.
Method: Double blind procedure
Procedure: 3 conditions-
1) highest level of cortisol, similar to major stress event, 160mg tablet.
2) low level of cortisol, same as minor surgical procedure, 40mg.
3) placebo group, tablet that looks the same but no cortisol. ( control group)
-Tested before taking cortisol, 1 day after, and six days after.
-Listen and recall prose paragraph for 6 days.
Findings: High cortisol levels impaired performance in memory tasks
- highest level had worst performance on verbal declarative memory.
-lowest had best showing link between levels of cortisol and memory.
Conclusion: high stress levels impair performance on memory tasks and verbal declarative memory
Explain one effect of one potential pheromone in human behaviour with reference to one study.
Pheromone = airborne chemical messengers released by the body that animals and humans use to communicate. Our bodies release pheromones through sweat, urine, semen, breast milk, and vaginal fluid. The theory is that these substances cause a reaction in the people around us. For example, pheromones might help us attract a mate.
- well documented in many animal species. humans is up for debate
- Compared to many other animal species, our sense of smell is far less developed, and we tend to rely on sight and sound far more than smell in most situations.
- If humans do have pheromones, they may simply be a leftover from our earlier evolution, and may not play much role in our behaviour. On the other hand, there is some preliminary evidence that suggests that human pheromones do exist.
Perception = the ability to see, hear, or become aware of something through the senses
ZHOU:
AIM = investigate how sex hormones can alter perception
PROCEDURE =
- the experiment involved 4 groups: heterosexual men, heterosexual women, homosexual men, and homosexual women
- participants viewed a walking human shape known as a “point light marker”. The gender of the human shape is ambiguous - it is not clear if its male or female. Participants had to say whether they thought the human shape was male or female.
- at the same time, unbeknown to the participants, the scent of either a male or female pheromone was released in the air (androstadienone, found in males sweat and semen, and estratetraenol, found in female urine)
RESULTS:
- participants responded to the pheromones of the gender they were attracted to when interpret the gender of the “point light marker”
CONCLUSION:
- Human pheromones do exist, and they seem to alert people to possible mating opportunities.
Explain the role of one gene in one behaviour with reference to one study.
Gene: Genes influence each individual’s behavioral and psychological characteristics, including intellectual ability, personality, and risk for mental illness.
- Base sequence of DNA (codes for the amino acid sequence of a polypeptide and a functional RNA)
- Genes carry information that gets passed from one generation to the next.
Serotonin transporter gene =
transports neurotransmitters serotonin from synaptic spaces into presynaptic spaces into presynaptic neurons. important role of pathophyiology of several psychiatric disorders
Caspi:
AIM = show evidence for a gene envirornment interaction for a mutation of the serotonin transporter gene.
METHOD = correlational study and SS sampling
PROCEDURE = new zealands who were members of a cohort that had been assessed for mental health on an every other year basis until they were 26 starting at 21. Split into three groups based on 5HTT allele.
Group 1 = 2 short alleles
Group 2 = one short and one large allele
Group 3 = two large allele
Participants then fill in a ‘stressful life events’ questionnaire which asked them about the frequency
FINDINGS:
people had inherited 1 or more short lesions of the of the allele which demonstrates more symptoms of depression and suicide ideation in response to stressful life events. Simply inheriting the gene is not enough to lead to depression, but the genes interaction with stressful life events increases ones chance of depressions. holisitic approach
Explain how genetic similarities help psychologists in the study of genes and behaviour with reference to one study.
Genetic similarities = measure of the genetic relatedness among individuals.
Monozygotic (MZ) twins = identical twins. develop from one fertilized egg, which splits and forms two embryos. They are genetically identical.
Dizygotic (DZ) twins = fraternal twins. they develop from two different fertilized eggs. they share 50% of their genes
Concordance rate = in twin research, the correlation found is called the concordance rate - the probability that the same trait will be present in both members of a pair of twins
Kendler:
AIM = to investigate the heritability of depression
METHOD = correlation (interviews; twin study)
PROCEDURE = the participants were interviewed and assessed for major depressive disorder in accordance with DSM-IV
RESULTS = The researchers estimated from the condordance rates in mono- and dizogotic twins that the heritability of depression is roughly 38% - The rate was higher in females. (MZ male - 31%: MZ female - 44%: DZ Males - 11% DZ females - 16%)
CONCLUSION:
Depression is somewhat heritable, but environment and stress play at least a big role (predisposition and stress: diathesis stress theory)
Explain the use of kinship studies or twin studies in the study of inheritance of behaviour, making use of one study.
Monozygotic (MZ) twins = identical twins. develop from one fertilized egg, which splits and forms two embryos. They are genetically identical.
Dizygotic (DZ) twins = fraternal twins. they develop from two different fertilized eggs. they share 50% of their genes
Concordance rate = in twin research, the correlation found is called the concordance rate - the probability that the same trait will be present in both members of a pair of twins
Kendler:
AIM = to investigate the heritability of depression
METHOD = correlation (interviews; twin study)
PROCEDURE = the participants were interviewed and assessed for major depressive disorder in accordance with DSM-IV
RESULTS = The researchers estimated from the condordance rates in mono- and dizogotic twins that the heritability of depression is roughly 38% - The rate was higher in females. (MZ male - 31%: MZ female - 44%: DZ Males - 11% DZ females - 16%)
CONCLUSION:
Depression is somewhat heritable, but environment and stress play at least a big role (predisposition and stress: diathesis stress theory)
Explain one evolutionary explanation of behaviour with reference to one study.
Evolution = the change in the characteristics of a species over several generations
Amygdala = part of the brain that’s associated with fear, emotions, and motivation.
The amygdala’s role in generating fear has helped us to survive
SM’s case study - Feinstein:
AIM = investigate the role of amygdala in fear processing
METHOD = SM. Women with genetic condition that caused damage to amygdala. She was asked to record diary and was presented with a variety of situations, that many people would feel fear (haunted house, horror movies, snakes, spiders). SM was also asked to fill in questionnaires about different aspects of fear (death, speaking in public) compared to a control group of healthy participants.
RESULTS = SM showed no fear response to horror movies, to dangerous animals or to the haunted house, reported not feeling any fear. Instead she felt excited and intrigued.
CONCLUSIONS = amygdala has an important role in the fear response, recognition and experiencing fear. Damage to the amygdala results in being unable to experience fear.
