Biological Flashcards
What is aggression?
Feelings of anger resulting in hostile or violent behaviour; readiness to attack or confront
What are the 3 main biological influences on our behaviour?
1) The Central Nervous System (brain, spinal cord, neurones)- this is a system of communication within the body
2) Evolution + Natural Selection - our behaviour is determined in genes that we inherit from our parents
3) Hormones- chemical messages that transmit information around the body in the blood stream. This can lead to psychological characteristics.
What is the Topic Overview of Biological Psychology?
Students must show an understanding that biological psychology is about the mechanisms within our body and understand how they affect our behaviour, focusing on aggression.
Individual differences and developmental psychology must be considered when learning about issues such as aggression caused by an accident and how the function of structures of the brain can be affected by the environment.
What is a Summary of Biological Psychology?
Biological psychology is about the brain as well as aspects of our physical make up such as genes, the idea of survival of the fittest, and hormones.
Your course will focus on aggression, looking at what parts of the brain relate to aggression and how hormones link to aggression, for example. More general biological issues are also considered including the theory of evolution.
What is the Structure of the Neurone?
http://study.com/cimages/multimages/16/600px-neuron1.jpg
Cell Body: energy is made here
Terminal Buttons: at the end of axon terminals; contain neurotransmitters
What is the Role of the Neurone?
The purpose of the neurone is to transmit messages around the body.
There are networks of millions of neurons in the brain and body that are all connected and communicate with each other.
How does Communication along Neurones happen?
- The dendrite receives a message, often from another neurone
- This triggers an action potential (electonic message within the cell body)
- This action potential travels down the axon. The myelin sheath & nodes of Ranvier help speed up the process
- The action potential reaches the axon terminals and terminal buttons
- The terminal buttons pass this message to the next part of the body. This could be another Neurone, a muscle or a gland.
What is the Structure of a Synapse?
http://article.sciencepublishinggroup.com/journal/160/1600972/image001.jpg
How are messages sent through the synapse?
- And electrical message (action potential) is sent along the axon of the presynaptic neurone
- Eventually it reaches the axon terminals
- Neurotransmitters are released into the synaptic cleft, and diffuse across the space between the two neurones
- The neurotransmitters attach to the receptor of the dendrite of the postsynaptic neurone
- When enough receptors are activated (the threshold is reached), a new action potential is created on the next neurone
- Any neurotransmitter that remains in the synapse is taken back into the presynaptic neuron in a process called reuptake
What is the Function of Neurotransmitters?
Different neurotransmitters are responsible for regulating different feelings and behaviours
What is the Role of Dopamine?
Dopamine is associated with pleasure reward and reinforcement.
It is involved in addictive behaviours.
It is also involved in posture and the control of movement
What is the Role of Serotonin?
Serotonin is involved with mood control and feelings such as happiness.
It is also involved in pain, sleep, temperature and hunger.
What is the Role of Norepinephrine/Noradrenaline?
Norepinephrine is associated with the fight and flight response, with attention, and being ready for action.
What is the Role of Acetylcholine?
Stimulate muscle contraction, and is involved in motor control the movement.
It is linked to memory, thinking and learning.
It is also involved in expressions of some emotions e.g. anger and sexuality.
What is the Effect of Alcohol on Behaviour?
Short-Term: Varies depending on the individual, the mood and their environment. It can reduce anxiety and inhibition, or make an individual more aggressive.
Long Term: It can be addictive, lead to liver failure and damage to the brain & nervous system
What is Alcohol’s ‘mode of action’?
Has a depressant effect on the CNS, by inhibiting messages in the neurones and synapses.
It does this by increasing GABA (an inhibitory neurotransmitter).
What are the Effects of Cocaine on Behaviour?
Highly addictive.
Short Term: Cocaine usually makes the user feel euphoric, energetic, talkative, and mentally alert. It’s can also temporarily decrease the need for food and sleep.
Long Term: Addiction, irritability and mood disturbances, restlessness, paranoia and auditory hallucinations.
What is Cocaine’s ‘mode of action’?
Cocaine acts on the dopamine reward pathways in the brain.
It blocks the reuptake process so that dopamine levels increase and the ‘message’ continues for longer.
What are the effects of Nicotine on Behaviour?
Highly addictive.
Short Term: Feelings of pleasure, a ‘kick’, feeling relaxed
Long Term: Cravings, irritability from withdrawal, cancer and heart disease
What is Nicotine’s ‘mode of action’?
Works on dopamine reward pathways in the brain.
It increases the amount of transmission of dopamine by blocking the enzyme that breaks it down
What are the effects of Ecstasy on Behaviour?
Short Term: Feelings of mental stimulation, emotional warmth, empathy towards others, a general sense of well-being and decreased anxiety
Long Term: Anxiety, restlessness, irritability, sadness, impulsiveness, aggression, sleep disturbances, lack of appetite, depression
What is Ecstasy’s ‘mode of action’?
Ecstasy increases levels of dopamine, serotonin and norepinephrine (especially serotonin)
What are the Individual Differences regarding the effect of recreational drugs on the transmission process in the CNS?
Neurotransmitters: people may have unusually high or low levels of certain neurotransmitters, which may predispose them to set a mental disorders. (Medication can be given to correct these levels)
Recreational Drugs: they are known to have different effects on different people. This may be due to biological differences in their brain structure and function
What is the role of the Hippocampus?
The hippocampus in involved in synaptic functioning; and is in the medial temporal lobe
What are the 4 Lobes?
Temporal
Parietal
Occipital
Prefrontal
- Lobes feature when studying the structure of the brain
What is the Corpus Callosum important for?
Taking messages between the 2 hemispheres of the brain
What is Evidence for the Link between the Prefrontal Cortex and Aggression?
- Lots of dopamine, serotonin and norepinephrine connections are found in the prefrontal cortex. These neurotransmitters link to emotions; suggesting the prefrontal cortex has a role in emotions
- Becharer + van der Linden (2005) agreed from their findings that the prefrontal lobe regulates behaviour + defers rewards, being about planning; lesion (damage) might be wanting more immediate gratification, making someone impatient, so linking to aggression. The prefrontal lobe inhibits messages from the amygdala, which links to it having a planning role + damage there might lead to more negative emotions
- Raine et al found that people who had showed emotional impulsive violence differed in their prefrontal cortex compared with controls
What is the Limbic System and how does it Link to Aggression?
- Limbic System: Hippocampus, Amygdala, Hypothalamus
- Has a role in Self Preservation; including response to emotions and the ‘Fight-or-Flight’ response, which arouses us when we’re in danger
- In animals, if the amygdala is stimulated (using an electric current), there is an aggressive response. If the amygdala is removed, the animal is passive
What is the Link between the Prefrontal Cortex and Aggression?
- Raine et al. found the prefrontal cortex is involved in aggression
- Aggression is due to a lack of control from the prefrontal cortex: If the prefrontal cortex is damaged, or functions poorly / abnormally, then people can become very impulsive, impatient and aggressive
- Depression links to the orbifrontal, vetromedial and lateral prefrontal cortex.
What is the Structure of the Pre-Frontal Cortex?
The prefrontal cortex is the outer layer of the brain, is in the prefrontal lobe, is found in both hemispheres and has a role in emotions
What are some Strengths of using Brain Functioning as an Explanation for Aggression as a Human Behaviour?
- Human case studies such as Phineas Gage are often consistent with the findings of animal studies; suggesting findings from lesion studies also apply to humans.
- Blair et al (2001) found that patients with psychopathic personalities have similar neurocognitive function to patients with a damaged amygdala; supporting the idea that this structure is linked to aggression
- Raine et al used PET scans and found that a group of murderers showed lower activity in the prefrontal cortex, and differences in the functioning of the limbic system (compared with controls); supporting the idea that these regions are involved in aggression.
- Psychology as a Science: Animal Research can be carried out in a more scientific way that with Human Research, due to ethics. High control is possible when manipulating/controlling variables- This leads to better internal validity, and a stronger cause + effect relationship
What is Evidence for the Link between the Limbic System and Aggression?
- Andy + Velamin (1978) stimulated the hypothalamus + basal ganglia (both in the limbic system) of cats; which lead to them having aggressive seizures.
- They also found that blocking catecholamines (epinephrine, norepinephrine and dopamine) increased aggression. This shows how neurotransmitters and brain structure link.
- Downer (1961) removed 1 amygdala from monkeys (ablation). Visual signals go to the amygdala- Visual signals that reaches the amygdala led to normal functioning, but when they went to the removed amygdala, this lead to more calm behaviour.
- Hermans et al (1994) showed that electrical stimulation of the hypothalamus leads to aggression.
What is Evidence for the Link between the Limbic System and Aggression?
- Andy + Velamin (1978) stimulated the hypothalamus + basal ganglia (both in the limbic system) of cats; which lead to them having aggressive seizures.
- They also found that blocking catecholamines (epinephrine, norepinephrine and dopamine) increased aggression. This shows how neurotransmitters and brain structure link.
- Downer (1961) removed 1 amygdala from monkeys (ablation). Visual signals go to the amygdala- Visual signals that reaches the amygdala led to normal functioning, but when they went to the removed amygdala, this lead to more calm behaviour.
- Hermans et al (1994) showed that electrical stimulation of the hypothalamus leads to aggression.
Who was Phineas Gage, and how does he Contribute to our Knowledge of Brain Structure and Aggression?
He had an accident in 1848, where a 3.1 pole went through his head from igniting compact explosive powder.
Scientists eventually established that up to 4 per cent of the cerebral cortex and about 11 per cent of the total white matter in the frontal lobe were destroyed.
(However, we mainly say he damaged his prefrontal lobe)
The wound physically healed in 10 weeks and he managed to live for another 11 years before he died.
In 1868 Harlow wrote a report on the ‘mental manifestations’ of Gage’s injuries. He described Gage as “fitful, irreverent, indulging at times in the grossest profanity…capricious and vacillating” and being “radically changed, so decidedly that his friends and acquaintances said he was ‘no longer Gage’.”
What are some Weaknesses of using Brain Functioning as an Explanation of Aggression as a Human Behaviour?
- The findings of animal research might not be generalisable to humans; as the effects on behaviour might be different in humans and animals
- Case studies such as Phineas Gage are not representative of society; and so findings may not generalise to everyone
- Brain scans used to find brain issues lack ecological validity
What is the Role of the Prefrontal Cortex?
The prefrontal cortex is involved with emotions and has high levels of synapses with dopamine, serotonin and norepinephrine)
It regulates behaviour and governs social interaction. It allows people to plan their actions and delay gratification and rewards
What’s the difference between ‘Whole Brainers’ and ‘Localisers’?
The whole brainers believed that the brain was linked. This means that they thought the all parts of the brain were in control of all emotions, instead of there being certain parts that are appointed to emotions. The localisers believed that certain parts of the brain controlled certain emotions.
What is Vital Force Theory?
The Vital Force is an energy that enables all living things to self-heal or to preserve life by adapting to environmental changes. In the case of the human body, the Vital Force directs the different body systems to function as a harmonious whole, in much the same way a conductor directs the separate parts of an orchestra to produce a single, pleasing piece of music.
What is the Unconscious mind?
The hidden part of our psyche (mind).
It contains thoughts, feelings and memories we are not aware of and we find hard to access/ can’t access. (e.g. someone may have repressed being lost as a small child, and not be aware of it)
There may be material that can never be recalled to the consciousness, in particular instincts + deeply buried memories.
What are our two instincts?
- The Libido/Eros: the life instinct that manifests itself as sexuality
- The Thanatos: the death instinct which manifests itself as aggression and destructiveness. These thoughts are inaccessible to us, to protect us from information that is unacceptable.
What are the Different Parts of Personality (according to Freud)?
Id, Ego and Superego
What is the Id?
The most primitive part of the personality that acts on instinctive drives + impulses with no thoughts of consequences.
It is driven by the Eros and Thanatos: Due to it being driven by the eros/libido (Pleasure Principle), it demands immediate gratification of its urges (food, sex, etc)
Humans are born with an id
(which explains why we crave food + comfort from an early age)
What is the Ego?
Driven by the Reality Principle (rules in terms of what is socially acceptable), and tries to satisfy the id within realistic appropriate boundaries
Develops at 2 years old
(at this point, the child doesn’t know right from wrong, but starts to understand when certain behaviours are appropriate)
What is the Superego?
Operates on the Morality Principle (understanding what is right and wrong)
Develops at 3-6 years old
(the child begins to feel guilt for wrongdoings, and pride for correct behaviour)
What is Catharsis?
Catharsis takes place when negative energy/emotions are released in the mind through relatively harmless activities. It satisfies the thanatos and unconscious.
(e.g. watching a horror film, or playing a violent video game releases violent tendencies without the individual actually harming someone in real life)
What research tested Catharsis?
Bushman (2002)
Student participants were told that another student had criticised an essay they had written, in order to annoy them.
They were then split into 3 groups; one sat quietly for a few minutes, one hit a punching bag, one hit a punching bag and were instructed to think about the student.
The third condition lead to angrier participants than the other groups.
How is the psychodynamic approach typically tested?
The psychodynamic approach typically investigated human behaviour through clinical case studies; in-depth investigations of an individual who presented an abnormal condition that was systematically studied over a long period of time.
What is Evolution?
The gradual development of different kinds of living organisms from earlier forms during the history of Earth.
This means that due to common ancestors, all species share some genes with each other.
How does Evolution happen?
By Natural Selection
- The process whereby organisms that are better adapted to their environment tend to survive and produce more offspring
- Organisms better adapted to the environment are healthier, live longer and reproduce more frequently; passing on the genes that made them reproductively fit onto their offspring
(eg, giraffes with longer necks pass on their genes to the offspring, as they are able to reach more trees and eat more)
What are Genes?
- A unit of hereditary information that is transferred from a parent to offspring, and is believed to determine a particular characteristic of the offspring.
What is sexual selection?
- A type of natural selection that occurs through preference by one sex for certain characteristics in individuals of the other sex.
- For example the evolutionary psychology stereotype would be that our female ancestors tended to choose tall muscular males who could protect them and their children, leading to those genes being passed on to the next generation
What is Mutation?
The changing of the structure of a gene, resulting in a variant (different) form which may be passed on to the subsequent generations
What does EEA stand for?
Environment of Evolutionary Adaptiveness
What is meant by EEA?
- The environment in which a particular adaptation is said to have evolved
- The conditions that prevailed in the environment at the time a species was adapted in response to
( e.g. The EEA for humans was when humans lived in Hunter-gatherer groups. In the EEA, successful humans were those best suited to the environment in which they lived)
How does Evolution Explain Behaviour?
- Evolutionary psychologists look at fossil records to understand the behaviour that would be adaptive. They then compare that to current behaviour in order to argue that behaviour is genetically determined through brain structure and chemistry
- Examples of behaviour that can explained within an evolutionary perspective include: parental investment, mate choice and understanding emotions.
- Unlike our genetic make up, our environment has undergone rapid change; leading to a potential mismatch where we stuck with ‘hardwired’ behaviour that would have served us well thousands of years ago but clashes with the way we live now
What is Parental Investment?
- The total energy and resources that parents must expand to produce a particular offspring
- The expenditure increases the survival of the offspring, but also decreases the ability for the parent to invest in other offspring
- The act of having sex can result in much higher parental investment for women, in comparison to males
- For males the minimum parental investment risk by copulation is the cost of sperm; for females the cost is nine months of pregnancy and the risks inherent in childbirth (and potentially more time and energy spent bringing up the children)
What is the link between Parental Investment and Mate Choice?
Some argue that these differences in parental investment between males and females lead women to be more selective with their mates than males
How does Evolution explain Aggression in Males?
- In the EEA, bigger and stronger males are the most capable of protecting their mates and offspring.
- Also, psychologically aggressive male would be more capable of doing this as they would be more successful at hunting, and defending food resources from other males
- These males also had an advantage in terms of mate choice: Females would prefer a male that could protect her, her offspring, and their food resources due to his aggressive nature.
- Therefore psychologically aggressive males would be more successful in reproducing, as they would be chosen by females as mates due to sexual selection.
How does EEA explain Females being Less Aggressive than Males?
- Physical aggression in females with that as an evolutionary disadvantage for their offspring: Females would have spent a lot of the time looking after vulnerable children; and if they engaged and fighting and hurting, this may well have put the lives of the children at risk.
- Therefore, aggressive females would be more likely to have offspring that did not survive to adulthood; and so their genes would not have continued, due to natural selection
- Evolutionary psychologists such Buss (1999) suggested females competed for the best mates through verbal and emotional aggression, by criticising other females and making them seem less attracted to males.
What are the advantages of using Evolution as an Explanation of aggression?
- Male brains have a small difference in structure in comparison to females, as the result of exposure to testosterone before and after birth. Some argue these differences are linked to male abilities e.g. spatial awareness (hunting/sport), and aggression; supporting the idea that aggressive males were more likely to pass on their genes, due to natural selection in the EEA.
- Mazur (1983) showed fighting between males increases at puberty, when testosterone levels in males increased dramatically; supporting the idea that male hormones (testosterone) are linked with aggression.
What are the disadvantages of using Evolution as an Explanation of Aggression?
- There is very limited evidence that evolution explains behaviour, and so we cannot experimentally/scientifically test the idea that aggressive males were more likely to pass on their genes due to natural selection in the EEA.
- Aggressive people are more likely to be injured or die as a result of their behaviour, which challenges the idea that aggressive males can pass on their genes
What are the issues and debates of using evolution as an explanation of aggression?
- Reductionism: Some argue it reduces the complex behaviour of aggression to being caused by particular genes that were favoured in the EEA; rather than explaining it more holistically, as caused by the interaction between the range of interconnecting factors (parts of the brain, social influences, cognitive processes, etc)
- Deterministic: some argue that explaining aggression through genes suggests we have little free will; and are programmed to behave aggressively by evolution. This can therefore be used as an excuse to explain aggressively and unacceptability:
for example some have used this theory to explain rape as an evolutionary strategy that was successful in the EEA so some men might be genetically predisposed to act in this way.
What is the Warrior Gene?
The so-called warrior gene comprises particular variations in the X chromosome gene that produces monoamine oxidase A (MAOA), an enzyme that affects the neurotransmitters dopamine, norepinephrine, and serotonin.
Studies have linked the “Warrior Gene” to increased risk-taking and to retaliatory behavior.
How are hormones Carried Around?
They are Carried in the Blood, and Operate All Around the Body
They take longer to work than neurotransmitters, and tend to be used to affect longer-term changes
What are Hormones?
Chemical Messages that Transmit Information around the Body
Where are Hormones Produced?
They’re Produced + Excreted by Glands; and the System of Glands is called the Endocrine System.
What is Oxytocin?
Released by the Posterior Pituitary Gland
Shown to Increase Trust between People
How do Hormones do within in the Body?
Hormones affect behaviour, and cause Physical Changes in the body
What is Testosterone?
An Androgen; which is a chemical that develops/ maintains male characteristics
We all have testosterone in our bodies, but it is much more present in Males than females.
What is Antenatal Exposure to Testosterone?
Antenatal exposure to testosterone has an organising effect on the developing brain, leading to increased spatial ability and (arguably) competitive aggression.
Following birth, testosterone sensitises certain neural circuits- e.g. stimulates cell growth in areas of the hypothalamus and amygdala, this affects aggression as an adult
What research supports antenatal exposure to testosterone?
Research on rodents support this:
1. Castration effectively stops testosterone production,and leads to little/no aggressive behaviour. However, if testosterone is injected afterwards, they’ll show aggression
- Testosterone injection in newborns will have a limited effect on their aggression. However, in those aged 10 days old, the replacement testosterone brings the level of aggression back up to normal for uncastrated rodents.
- Injecting neonatal female rodents with testosterone made them act more aggressively when given testosterone as adults, compared to control females
What is Adrenaline, and where is it produced?
Adrenaline is produced in the medulla in the adrenal glands, as well as some of the central nervous system’s neurons.
Within a couple of minutes during a stressful situation, adrenaline is quickly released into the blood, sending impulses to organs to create a specific response.
