3.1 content (biological) Flashcards
1
Q
what are genes?
A
instructions on how to make proteins
2
Q
what are hormones?
A
- chemical messengers that travel in the blood
- it is slow
3
Q
what are neurotransmitters?
A
- chemical messengers that act in the synapse
- very fast
4
Q
what is the definition of aggression?
A
- behaviour that is intended to cause injury, both physical and psychological
- way to assert or maintain dominance
5
Q
what is the frontal lobe responsible for?
A
for higher order reasoning, decision making and impulse control
6
Q
what is the parietal lobe responsible for?
A
sensation and movement
7
Q
what is the temporal lobe responsible for?
A
emotion and memory processing
8
Q
what is the occipital lobe responsible for?
A
vision
9
Q
what is the limbic system?
A
- contains amygdala which regulates emotional responses
- role in memory and learning
- connects cortical and subcortical regions of the brain
10
Q
what does the hypothalamus do?
A
- hunger, thirst and sex motivational drives
- role in body’s fight or flight stress response
- maintains functions in the endocrine system by secreting hormones and manipulating pituitary gland
11
Q
what does the spinal cord do?
A
- long, tubelike structure that starts at the end of brain stem and finishes at the bottom of the spine
- consists of nerves that carry messages between the brain and rest of body
12
Q
what is the function of cell body in a neuron?
A
contains nucleus which contains the genetic material of the cell
13
Q
what is the function of dendrites?
A
- receives neurotransmitters from neighbouring neurons towards the cell body
- it has receptors which bind to specific neurotransmitters
14
Q
what is the function of the axon?
A
- tube like structure that carries an electrical impulse in the cell body
- impulse generated in the axon hillock
15
Q
what is the function of the myelin sheath?
A
insulate the axon and make impulses travel faster
16
Q
what is the function of terminal buttons?
A
- ends of the axon
- involved in communicating with neighbouring neurones by releasing neurotransmitters into the synapse
17
Q
what’s the function of a neurone vesicle?
A
neurotransmitters are stored here
18
Q
what are the steps of neurotransmitters travelling through neurons?
A
- dendrites have receptors which receive neurotransmitters, they are attached to the cell body
- electrical impulse travels down the axon, it is generated at the axon hillock
- axon is covered in myelin sheath which speeds up impulses
- it travels down the terminal button. terminal button has vesicles filled with neurotransmitters
- neurotransmitters diffuse down the synapse
19
Q
what is the function of a sensory neuron?
A
carries sensory information from the body to the brain
20
Q
what is the function of the motor neuron?
A
carries signal from the brain that makes muscles in the body move
21
Q
what is the relay neuron?
A
connects to motor and sensory neurons
22
Q
what is excitation?
A
signals from neighbouring neurones that make the neuron’s charge more positive
23
Q
what is inhibition?
A
signals sent from neighbouring neurones that make the neurons charge more negative
24
Q
what is cancellation?
A
excitatory and inhibitory signals from neighbouring neurones cancel each other out
25
what is spatial summation?
**many neighbouring neurones** send **excitatory signals** to the neurone
26
what is temporal summation?
**one neighbouring neurone** send **many excitatory signals** to the neurone
27
how does cocaine work?
- **affects the dopamine** reward system in the **brain**
- **mimics the structure of dopamine molecules** and **blocks receptors at the terminal buttons** leading to dopamine molecules staying in the synapse
- leads to a **large build up of dopamine** binding to the **postsynaptic neurone**
- **person feels pleasure** but it **leads to body’s dopamine system being deregulated** leading to **weight loss and dry mouth**
28
how does heroin work?
- **affects endorphins** and natural painkillers **in the brain**
- **mimics structure of endorphin molecules** in the neurons, leading to **many mu receptors being activated**
- this **produces excess levels of endorphins** leading to **pleasure experienced by the person**
- leads to **pain after being high** as **body lowers the endorphin levels** to compensate
29
what’s the function of the amygdala?
- part of the brain that **processes emotion regulation and motivation**
- plays a central role in **how an organism assesses and responds to threats and challenges**
- **coccaro** found that **people who have extreme aggression** show much **higher levels of amygdala activity**
30
how does the frontal lobe (prefrontal cortex) link to aggression?
- **governs most social interactions** and **regulates behaviour**
- **ability to control impulses** is associated with it
- **raine** found that **murderers had higher levels** of activation in their **amygdala** but **lower in the prefrontal cortex**
31
how is the hypothalamus linked to aggression?
- produces the **fight or flight response** and **activates** the **sympathetic nervous system** + **adrenal-cortical system**
- sympathetic nervous system **speeds the body up** and it **becomes alert**
- adrenal-cortical system leads to **adrenaline being released** which **increases heart rate**
32
what is serotonin and how is it linked to aggression?
- inhibitory neurotransmitter
- **normal levels** of serotonin are associated with **reasonable levels of self control**
- **low levels** of serotonin are related to **lower levels of control** and **more violent impulses such as aggression**
33
what is dopamine and how is it linked to aggression?
- **neurotransmitter** that gives experiences of **reward**
- **increased level of dopamine** overall **increased aggression** but when **combined with a lower level of serotonin** the **aggressiveness increases even more**
34
what is localisation of function?
**specific areas of the brain** are involved in **specific tasks**, such as **amygdala** being responsible for **threat perception**
35
what was the aim of raine’s study?
**to investigate** whether the brain areas of the **prefrontal cortex, angular gyrus, amygdala, hippocampus, thalamus and corpus callosum** were **related to violent behaviour**
36
what’s the role of the hippocampus
helps with **learning and memory**
37
what’s the role of the thalamus?
**relays sensory and motor signals** to and from the **brain**
38
what’s the role of the corpus callosum?
connects left and right cerebral hemispheres
39
who were raine’s participants?
- **41 murderers** who used the **NGRI defence** in their trials
- **41 age, ethnicity and sex matched** controls to **each murderer**
40
what was the procedure of raine’s study?
- **each participant** was given a **radioactive tracer injection** into their **blood**
- **tracer chemical** will make **areas** of the brain **undergoing metabolism light** up
- **32 mins after** tracer is injected, **participants have to do tasks** on a computer, moving a button etc.
- **tasks activate areas** in the brain researchers are interested in
- after the tasks a **PET scan was taken and took 10 images** of tha brain at **10mm intervals**
41
what were the results for raines study?
- **murderers had less activity** in the **prefrontal cortex** than the controls
- **graphs** to show **less glucose level for murderers**
42
what was the conclusion of raine’s study?
-**murderers who were pleading NGRI** have **different brain activities** than **people who were not violent offenders**
- suggests that **no single brain area** is **related to violent behaviour** but **various areas interact together** to lead to **violent behaviour**
43
what’s a strength of raine’s study?
- high levels of **control**
- **standardised procedures** were used (same tasks) , participants were **drug tested** and the **PET scanning method were consistent** across participants
- therefore, the **internal validity of the study was high**, **confounding variables** were all **controlled**
44
what’s a weakness of raine’s study?
- some key elements weren’t controlled
- **23 of the murderers** had suffered from **head injuries** which could’ve explained the **differences in corpus callosum activities**
- **situational factors** like **upbringing** could have also **affected the brains** of the participants
- therefore, **researchers cannot be absolutely certain** that **other factors other than brain structure** could have **lead to violent behaviour**
45
how is testosterone linked to aggression?
- linked to **fight or flight** response
- hormone **linked to aggression**
46
how’s cortisol linked to aggression?
- **hormone produced** in the **adrenal gland**
- **manages stress levels** which inhibits aggression
47
what’s a strength of hormonal explanations for aggression?
- Dabbs et al
- **measured testosterone** in **saliva of 692 adult male prisoners** and he found **higher levels in rapists and violent offenders**
- therefore, testosterone is linked to aggression
48
what’s a weakness of hormonal explanations for aggression?
- evidence is correlational
- research **just considers the changes in hormone levels** in **association with changes in aggression**, without **manipulating hormone levels** to see **if they cause changes in aggression** as it’s **unethical**
- therefore, **impossible to establish a casual relationship** meaning there could be **alternate explanations** such as **increased testosterone levels**
49
what’s natural selection?
- **some mutations are better suited** for the **environment** the living thing is in
- those with **useful mutations survive** better in that environment and **more likely to pass on their genes**
- **traits and behaviours** are **adapted and changes** in species over time
50
hows aggression useful as an evolved trait?
- helped **our ancestors gain territory** and **resources**
- used in **hunting and providing food** for others
- **scare off potential competitors** or fight for **resources for survival**
- **males** have developed strategies for **guarding their female partner** so that **their genes are passed on and not the rivals**’
51
what’s a strength of evolutionary explanations for aggression?
- Chester
- found that in **277 male and female participants**, lower functioning **MAOA genes lead to less inhibition and self control** — more aggression
- therefore, it **supports evolutionary theory** as aggression can be linked to **inheriting certain genes**
52
what’s a weakness of evolutionary explanations for aggression?
- Wolfgang
- found that **kung san people** have very **low levels of aggression** as **behaviour is discouraged** from childhood
- therefore, **aggression can be outweighed by cultural norms**
53
how are CT scans done?
- **uses X rays** that **pass through the brain** in multiple angles
- **computer creates an image** of the brain
- **measures what areas of the brain are damaged** or **where tumours** are positioned
54
what are the risks with a CT scan?
damage unborn babies
55
what are the advantages of a CT scan?
- **very quick** to conduct showing **accurate details of brain structure**
- quality can **show tumours** or **structural damage** that could **lead to better understanding** of the area
56
what are the disadvantages of a CT scan?
- **can’t tell you** about **how the brain is functioning** and only provides structural information
- **limited use in research** linking brain areas to specific behaviours
57
how does a PET scan work?
- **injected with radioactive tracers** that is **absorbed into bloodstream** and **binds to glucose molecules in the blood**
- **high conc. of gamma rays** found in **areas of high activity** in images
- **measures glucose levels** in the brain: more glucose used = more activity
58
what are the risks of a PET scan?
low risk but is unclear whether there will be long term effects
59
what are the advantages of PET and MRI scans?
- **indicate specific areas** of the brain **involved in an experience**
- provide **evidence** of **localisation of function**
60
what are the disadvantages of PET and MRI scans?
**low mundane realism** —> tasks done by patient artificial and **not everyday tasks**
61
how do MRI scans work?
- very **powerful electromagnet** is used, **blood cells with oxygen** will **repel magnet** but ones with **no oxygen will follow** it
- **areas** of the brain that **use more oxygen** are **more active** and you can see which **areas are being used in tasks**
62
what are the risks of an MRI scan?
people who have **metal surgical implants and pacemakers cannot** go through an MRI
63
what are overall benefits of using brain scans?
- **reliable and objective ways** to **measure brain activity** or **structure**
- we can **establish connections** between **brain areas and behaviours** by comparing measurements against behaviour
64
what are the overall issues with using brain scans?
- tasks are **generally low in mundane realism** and **may not trigger or activate** the brain in the **same way real behaviour would**
- **e.g** activity on a computer vs being aggressive irl
- therefore, **findings on brain activity may not be applicable**
65
what are the two components of the id?
Eros: a **desire to preserve life** and enjoy it
Thanatos: a **drive towards death and destruction**
66
what’s the id’s role?
- stands for **inner drive**
- **formed** from the **desires of Thanatos and Eros** with no thought for consequences
- **pleasure principle**: to gain pleasure or **satisfaction of urges asap**
- eros eg = food, thanatos eg = aggression
67
what’s the superego’s role?
- **socialised part** of your personality developed through the **way you were raised**
- **morality principle**: socialised understanding of what’s **right and wrong**
- **demands you to follow your morals**, if someone **follows their id** they will **feel guilty** but if they **control** then they’ll **feel pride**
68
what’s the ego’s role?
- driven by the **understandings of reality**
- **urges** of the id **cannot always be immediately satisfied**
- **reality principle**: understanding what’s **socially or realistically acceptable** to achieve
- **redirects id’s desires** to a more realistic behaviour: **sublimation and/or displacement**
69
what’s displacement and sublimation?
displacement — when **aggression towards someone** is **not acceptable** so you **redirect it** towards someone more acceptable (eg younger sibling)
sublimation — when **someone displaces their emotions** in a **socially acceptable way** (eg ranting in ur notes app)
70
what’s a strength of freud’s explanation?
- Graham
- those who **ranted and processed emotions and aggression** had an **improvement in control over pain**
- therefore, **processing aggression can be beneficial in the long term**
71
what’s a weakness of freud’s explanation?
- **freud’s concept** of **letting off steam** has been **shown to actually heighten aggression** by **bushman**
- **600 students got angry** because a **confederate heavily criticised their essays**
- students who were **allowed to release anger** by **hitting a punching bag** were the **most aggressive** with confederate
- therefore, **venting can heighten aggression** and **lead to antisocial behaviour**
