Biopsychology Flashcards
1
Q
What does low levels of serotonin mean?
A
Depression
2
Q
What do high levels of dopamine mean?
A
SZ (type 1)
3
Q
What do high levels of melatonin mean?
A
Sleepiness
4
Q
What does high adrenaline mean?
A
Stress
5
Q
Parts of the brain and it’s functions (6)
A
Frontal lobe - thinking,memory, behaviour and movement
Temporal lobe - hearing, learning and feelings
Brain stem - breathing, heart rate and temperature
Cerebellum - balance and coordination
Occipital lobe - sight
Parietal lobe - language and touch
6
Q
What is a genotype?
A
They only determine the potential for characteristics genetic makeup.
7
Q
What is a phenotype?
A
The observable characteristics of an individual depend on the interaction of genetic and environment factors.
8
Q
Overview of the endocrine system
A
- Endocrine system is separate from the nervous system, although the two work together.
- It works with the nervous system to control the vital functions in the body. The endocrine system acts more slowly than the nervous system, but has very widespread and powerful effects.
- The main aim of the endocrine system is to maintain homeostasis.
9
Q
What are hormones?
A
- The chemicals circulate in the blood and carry them to the target sites throughout the body.
- A given hormone usually affects only a limited number of cells nearest target cells.
- There has to be particular receptors for particular hormones, so they don’t have such a receptor cannot be directly influenced by that hormone.
- When enough receptor sites are stimulated. This results in the physiological reaction to go to target cell.
10
Q
Pituitary gland
A
- Next to the hypothalamus
- Secretes LH and FSH which stimulate the ovaries to produce oestrogen and progesterone and testes to produce testosterone and sperm.
11
Q
Adrenal gland
A
- On top of each kidney
- Secretes adrenaline - prepares the flight or fight response
12
Q
Testes
A
- In the scrotum
- Secretes testosterone
13
Q
Ovaries
A
- In the uterus
- Secretes oestrogen and progesterone - controls the menstrual cycle.
14
Q
Thyroid gland
A
- Below the Adam’s apple
- Secretes thyroxine - controls the rate of metabolism
15
Q
Thymus gland
A
- Above the heart
- Secretes thymosin - stimulates development of T cells
- Part of the immune system and functioning
16
Q
Pancreas
A
In the pancreas
- Secretes insulin and glucagon which regulates the blood sugar
17
Q
Pineal gland
A
- In the brain next to the thalamus.
- Produces melatonin which helps regulate the wake-sleep cycle.
18
Q
What it is the CNS
A
The Central nervous system consists of the brain and spinal cord.
19
Q
What it is the PNS?
A
The peripheral nervous system is everything apart from the CNS.
20
Q
Nervous system
A
CNS - PNS
|
SNS ANS
|
Sympathetic - Parasympathetic
21
Q
Localisation of function of brain:
A
The brain has a particular part that is in charge of a specific behaviour.
22
Q
Franz Gall’s theory:
A
Phrenology (looking at the structure of the skull to determine a person’s character) was influential, but quickly discredited.
23
Q
Phineas Gage:
A
- Provided evidence for localisation of function.
- Prior to accident was nice/friendly.
- After accident he was mean/aggressive, different character.
- Pole went through the top of his brain.
24
Q
Corpus Callosum
A
Bridge between the 2 hemispheres.
25
Motor cortex:
- Located in frontal lobe, both hemispheres.
- Allows to produce voluntary movement, sends info out.
- Damage (stroke/accident) to this area results in loss of control over fine movements.
- Different parts of the motor cortex control different parts of the body.
- These are arranged logically - the region that controls the foot is next to the region that controls the leg.
26
Somatosensory cortex:
- Detects sensory events, dedicated to the processing of sensory info related to touch.
- Uses sensory info to produce sensations such as: touch, pressure, pain, temperature.
- The amount of somatosensory area devoted to a particular body part denotes its sensitivity. Receptors in our face + hands occupy over 1/2 of the somatosensory area,
27
Visual centres:
- Located in the occipital lobe.
- Visual processing begins in the retina.
- Nerve impulses from the retina travel to areas of the brain via the optic nerve.
- Some travel to areas of the brain involved in coordination of circadian rhythms.
- Most terminate in thalamus, this acts as a relay station passing info to visual cortex.
- Each eye sends info from the right visual filed to the left visual cortex and the other way. This means damage to the left hemisphere can produce blindness in the right visual field.
- Visual cortex contains different areas that process different types of visual info such as colour, shape, movement.
28
Auditory cortex:
- In temporal lobes on both sides of the brain.
- Begin in cochlea in inner ear, sound waves are converted to nerve impulses.
- These travel via the auditory nerve to the auditory cortex.
- Pit stop at the brain stem where basic decoding happens.
- Then at the thalamus which acts as a relay station and carries out further processing of auditory stimulus.
- Stops at the auditory cortex.
- Sound has already been largely decoded by this point, in the auditory cortex is recognised and may result in an appropriate response.
- Damage may produce partiL hearing loss; the more extensive the damage, the more extensive the hearing loss.
29
Karl Lashley, evidence against localisation:
- Taught rats to do a maze quickly.
- Started destroying parts of the cortex, the the rats still retained parietal memory of the maze.
- He concluded that memory was not localised, but lies in a number of locations.
- No area was proven to be more important than any other.
- Called this the law of mass action.
30
Evaluation of localisation:
• Functions such as language are too complex to be assigned to just one area and instead involve networks of brain regions.
• Issues generalising from case studies or from ‘abnormal’ patients
• Issues with generalising from studies with small participant numbers
• Lashley proposed the equipotentiality theory, which suggests that the basic motor and sensory functions are localised, but that higher mental functions are not.
• Tulving et al (1994) revealed semantic and episodic memories reside in different parts of the prefrontal cortex.
31
Broca’s area:
- An area of the frontal lobe of the brain in the left hemisphere (in most people) responsible for speech production.
- Production of articulate speech, clear and fluent.
- Moves the muscles that are required to speak.
- Involved in analysing the grammatical structure of sentences, helps us extract meaning from language.
32
Discovery of Broca’s area:
- 1880’s
- Paul Broca identified small area in the left frontal lobe responsible for speech production.
- Treated patient call ‘Tan’ and other 8 patients with similar language deficits.
- All of them agreed to give their brain to Broca to analyse post-mortem.
- Neuroscientist have found that when people perform cognitive tasks (no language/speaking) their Broca is active.
33
Dronkers et al:
- Conducted MRI scan on Tan’s brain, trying to confirm Broca’s findings.
- Although there was a lesion found in Broca’s area, they also found evidence to suggest other areas may have contributed to the failure in speech production.
- These results suggest that the Broca’s area may not be the only region responsible for speech production and the deficits and found in patients with Broca’s aphasia could be the result of damage to other neighbouring regions.
34
Wernicke’s area:
- An area of the temporal lobe in the left hemisphere responsible for language comprehension.
- Vital for locating appropriate words from memory to express meaning.
35
Discovery of Wernicke’s area:
- Identified patients who had no problem pronouncing language but severe difficulties understanding it.
- Wernicke’s proposed that language involves separate motor and sensory regions located in different cortical regions.
- There is a neuro pathway between Broca’s and Wernicke’s area.
36
Turk et al:
- Discovered a patient JW, who suffered damage to the left hemisphere but developed the capacity to speak in the right hemisphere, eventually leading to the ability to speak about the information presented to either side of the brain.
• This suggests that perhaps localisation is not fixed and that the brain can adapt following damage to certain areas.
37
Localisation:
How much any one function is located more in one hemisphere than the other.
38
Frontal lobe:
- Movement
- Consciousness
- Speech production
- Personality
39
Parietal lobe:
- Perception
- Sensory information (5 senses)
40
Occipital lobe:
- Visual information
41
Temporal lobe:
- Speech recognition
- Hearing
42
Lateralisation
How much any one function is located more in one hemisphere than the other.
The idea that the two halves of the brain are functionally different and that each hemisphere has functional specialisation.
43
Sperry split brain research, aim:
To examin the effects of disconnecting the brain’s 2 hemisphere on peoples behaviour.
44
Sperry split brain research, method:
- 11p’s in quasi experiment
- P’s corpus callosum disconnected.
- Apparatus was used which could send info to one hemisphere
- The patients VF were split.
- Visual stimuli were projected for 1/10th of a second, which is too fast for eye movement (so info can’t go to the ‘wrong’ hemisphere)
45
Sperry split brain research, results:
- The disconnected hemispheres didn’t effect p’s behaviour, IQ, personality.
- Hemispheres have different abilities/functions
- One hemisphere does not know what the other has seen or felt.
46
Sperry split brain research, conclusion:
Sperry concluded that the 2 hemispheres have different functions and that split brain patients have
47
Brain plasticity:
The ability to change and adapt because of experience.
48
How memories are made:
- New neural pathway is created after we learn something new.
- This neural pathway is fragile/weak.
- Can be strengthened through repetition/revision.
49
Synaptic pruning:
The deletion of rarely used connections.
50
Functional recovery:
The transfer of functions from a damaged area of the brain after trauma to other undamaged areas.
51
Neuronal unmasking:
- Activation of ‘dormant’ synapses to compensate for damaged areas of the brain.
- The dormant synapses receive higher input due to damage elsewhere.
- This cause new pathways to open.
52
Axonal sprouting:
- New nerve endings grow and connect with undamaged areas.
- It creates new blood vessels and pathways around the damaged area.
- With neural pathways this is just growing new nerve endings to join undamaged neruons, creating new pathways.
53
Reformation of blood vessels:
- Supporting and reinforcing new connections with blood vessels.
54
Recruitment of homologous areas:
- The brain takes on the opposite hemisphere to do specific tasks.
- This structural change might be using existing structures on the opposite hemisphere to enable a route to be used without having to build new networks.
55
Denervation super-sensitivity:
- Axons with a similar function to the damaged ones, are more aroused and more sensitive to input.
- Loss of nerve supply to a particular area of the body, results in an increase in the sensitivity of the remaining nerves in that area.
- The nerves that used to supply the limb are no longer present, but the remaining nerves in the area become hypersensitive.
- Phantom limb occurs when retiring takes place in the brain but it overcompensates.
56
Plasticity research/studies:
- Maguire et al (2000), black cabs
- Elbert et al (1985), professional violinists
- Daniel (2013), left hemisphere removed
57
Plasticity, Maguire et al (2000):
- To become licensed, black cabbies must show a thorough knowledge of streets and monuments in London.
- The demands on long term memory as well as spatial reasoning were particularly significant as this was ore satnavs.
- Brain scans of 16 London taxi drivers showed a large posterior hippocampus, a region of that brain that supports two-dimensional spatial processing.
- The posterior hippocampus was largest in taxi drivers with more than 40 years of experience navigating the streets of London.
- Increased grey matter was found in the brains of the taxi drivers compared with controls in the two brain regions, the right and left hippocampi.
58
Plasticity, Elbert et al (1985):
- A professional viol relies on extraordinary finger dexterity in their left hand.
- Much less dexterity is required in the fingers of the right hand, which is responsible for bowing.
- Brain scans of the somatosensory cortex in violinists reveal an unusually large region devoted to the fingers of the left hand.
- The asymmetry suggests that the brain has responded to the demands placed upon it - the brain adapts by recruiting neurons to help support the finger control in the left hand.
59
Functional recovery, Danielli (2013):
- Investigated an Italian boy EB who had most of his left hemisphere removed at age 2 1/2 to remove a tumour.
- With intensive therapy EB’s right hemisphere was able to take over left hemisphere functions such as language and speech due to EB’s maximal plasticity as he was young.
60
Negatives of plasticity:
- Examples: prolonged drug use leading to poorer cognitive functioning and in old age being associated with dementia.
- Both are due to changes in the brain.
61
Evaluation of plasticity, age:
- Hart (2014) found that the recovery was slower as age increases and was influenced by the severity of the impairment caused by the injury.
- Elbert et al. concluded that the capacity of neural reorganisation is much greater in children that in adults, meaning that neural regeneration is less effective in older brains. This might explain why adults find change more demanding this;do young people.
62
Evaluation of plasticity, gender:
- Research has shown women recover quicker than men.
- It’s a commonly accepted view that functional plasticity reduces with age (Huttenlocher).
- According to his view, the only option following traumatic brain injury beyond childhood is to develop compensatory behavioural strategies to work around the deficit (such as seeking social support or to develop strategies to deal with cognitive deficits).
- However, studies have suggested that even abilities commonly thought to be fixed in childhood can still be modified in adults with intense retraining.
63
Evaluation of plasticity, education:
- Schneider found that patients with a uni education are 7x more likely that those who didn’t finish school to be disability free 1 year after a moderate to sever traumatic brain injury.
- A retrospective study, 769 studied, 214 had achieved disability free recovery (DFR) after 1 year.
- Of these (214), 39.2% of the patients with 16 or more years of education had achieved DFR, as had 30.8% of those with 12 to 15 years of education, and just 9.7% of those with less than 12 years of education achieved DFR after just one year.
- Schneider concluded that ‘cognitive reserve’ could be a factor in neural adaptation during recovery from traumatic brain injury.
64
Invasive method meaning:
An invasive procedure is when the body is ‘invaded’ or entered by a needle, tube device, or scope.
65
Post mortem:
- An invasive method.
- Examination of a corpse in order to study the relationship between brain and behaviour.
- Tries to correlate abnormalities/damage to behaviour.
- Broca’s and Wernicke’s area discovered through this method.
- May lack validity due to small sample.
66
FMRI:
- Functional Magnetic Resonance Imaging
- Non invasive method.
- 3D scans using magnetic and radio waves.
- They measure brain activity tracking blood flow.
- It measures the change in energy released by haemoglobin reflecting activity of the brain (oxygen consumption).
- The person lies in a large cylinder magnet and radio waves are then sent through the body, affecting the body’s atoms and so a moving picture of the brain is produced.
- Captures dynamic brain activity as opposed to MRI/post mortem which only show physiology of brain.
- Good spatial resolution
- Expensive, implications on the economy.
- Interpolation difficult and affected by temporal resolution due to 5s delay.
67
EEG:
- Electroencephalogram
- Non invasive
- Measures electrical activity in the brain.
- When the brain cells send messages to each other, they produce tiny electrical signals.
- In an EEG test, electrodes are placed onto the scalp using a sticky substance.
- These electrodes pick up the electrical signals/neural activity from the brain and send them to an EEG machine, which will record the signals on a computer screen which clinicians then monitor.
- Cheaper than FMRI
- Non invasive method so ethically good
- Good temporal resolution.
- Poor spatial resolution
68
ERP:
- Event Related Potentials
- Measuring the brain’s response to stimulus through analysis of EEG data in response to a stimulus.
- Using a average of the original EEG recording researchers can filter out all other brain activity apart from what they are interested in this is an ERP.
- ERP’s that occur within 100 milliseconds are sensory ERP’s.
- Over 100 millisecond are cognitive ERP’s.
69
Biological rhythms:
A change in processing due to changes in the environment (external and internal).
70
Circadian rhythms:
- A biological rhythm that occurs approximately once every 24 hours.
- Needed to balance behaviour and body states.
- The sleep/wake cycle is an example.
71
Endogenous pacemaker:
The body’s internal body clock that regulates biological rhythms eg: SCN' which detects light.
72
Exogenous zeitgebers:
External factors in the environment which rest our biological clocks eg: light, social cues.
73
Super charismatic nucleus - SCN:
- A tiny bundle of nerve cells located in the hypothalamus (coordinates F or F).
- One of the primary endogenous pacemakers.
- Helps to balance sleep/wake cycle
- The master clock
74
Animal studies for circadian rhythms:
- DeCoursey et al, chipmunks
- Martin Ralph et al, hamsters
75
DeCoursey et al, animal study for circadian rhythms:
- 30 chimps is had SCN connections destroyed who then were then returned to their natural habitat for 80 days.
- The sleep/wake cycle disappeared and a significant portion of them were killed.
76
Martin Ralph, study for circadian rhythm:
- Bred ‘mutant’ hamster with a 20 hour sleep/wake cycle.
- SCN tissues were transferred to brains of normal hamsters, the second group’s cycle defaulted to 20 hours.
77
Michel Siffre - Cave study (1):
- 1962, spent 2 months living in total isolation without a clock/calendar/sun, only had a small light.
- Sleeping and eating only when his body told him to, his goal was to discover how the natural rhythms of human life would be affected by living ‘beyond time’.
- Emerged on 17th September, thought it was 20th August - he overestimated.
- His natural rhythm extended to over 25 hours, supporting endogenous pacemakers.
78
Michel Siffre - Cave study (2):
- Went a second time and lived for 7 months.
- Settled in a sleep/wake cycle of 25 to 30 hours.
- Supports the assumption that endogenous pacemakers exert an influence on circadian rhythms.
- Slowing the strength of circadian rhythms as a free running cycle and questions the extent to which it can be overridden by exogenous zeitgebers.
79
Ultradian rhythms:
- Occurs under 24 hours.
- Example: stages of sleep, which lasts approximately 90 minutes and there’s 5 stages.
- An EEG can be used to look at this
80
Stage 1 and 2 of sleep:
- ‘ Sleep escalator’, are light sleep where the person may be easily woken.
- At the beginning of sleep, brainwaves start ti slow down and are alpha waves,
- Stage 2 ends with theta waves, and deeper sleep.
- Non REM sleep.
81
Stage 3 and 4 of sleep:
- Both non REM.
- Involve delta waves with are slower still.
- Difficult to wake someone up.
82
Stage 5 of sleep:
- REM sleep (Rapid Eye Movement)
- Body is paralysed
- Brain is hyperactive
- Memories are processed, dreams occur here,
- If someone wakes up and remembers their dream they awoke during Stage 5.
83
Dement and Kleitman - stage of sleep:
- Measured pps brain activity using EEG controlling for the effects of affine and alcohol.
- REM sleep was highly correlated with dreaming, the more vivid the more active.
- Waking pps up during the REM stage, people could recall very clearly what they dreamed.
84
The Basic Rest Activity:
- Kleinman argues this continues during the day, when we’re awake.
- Instead of sleep stages, we move from states of alertness into a stage of fatigue, approximately every 90 minutes.
- The human mind can concentrate for 90 minutes, towards the end of this body begins to run out of resources.
85
Non REM sleep:
- For the restauration of the body.
- Marked by a reduction of physiological activity as bodily functions slow down.
- There are three phases of non REM sleep: N1,N2,N3.
- Each stage is marked by unique characteristics and différés from the others in terms of the depth of sleep.
- During non REM sleep, electrical activity in the brain slows, growth hormone, secretion occurs, and there is a decrease in muscle activity, heart rate, respiration, and oxygen consumption (Purves et al. 2001)
86
REM sleep:
- Heavily regulated by the brain stem.
- Deepest sleep
- Motor neurons don’t work during this stage,
- After a brain trauma people spend longer in REM sleep.
- REM sleep is for the restauration of the brain.
87
Infradian rhythms:
- Last longer than 24 hours.
- Example: female menstrual cycle, SAD.
88
The female menstrual cycle:
- Takes 24 to 35 days
- Hormones: oestrogen and progesterone.
- Governed by hormones, endogenous pacemakers.
- Cycle begins when the womb lining sheds.
- During each cycle, rising levels of oestrogen will rice causing the ovary to develop Ann egg and release it (ovulation).
- After ovulation, the progesterone helps the womb lining to grow thicker, readying the body fro pregnancy.
- Of pregnancy doesn’t occur, the egg is absorbed into the body, the womb lining comes away and leaves the body (menstrual flow).
89
McClintock and female menstrual cycle:
- 29 women with a history of irregular periods.
- Sample of pheromones are gathered from 9 of the women at different stages of their menstrual cycles, via a cotton pad placed in the armpits.
- The pods were worn for 8 hours to ensure that pheromones were picked up.
- The pods were treated with alcohol and frozen, to be rubbed on the upper lip of other pps.
- On day one, pads from the start of the menstrual cycle were applied to all 20 women, on day two they were all given a pad from the second day of the cycle, and so on.
- 68% of women experienced changes to their cycle which brought them closer to the cycle of their ‘odour donor’.
90
SAD (Seasonal Affected Disorder):
- Longer nights = increases melatonin secretion
- Linked to increase in depressive symptoms
- If a lack of sunlight creates depression in some people, phototherapy has been found to be an effective treatment.
91
SAD, study:
- 96 patients randomly assigned with winter SAD to one of 3 bright light treatments that are 10 to 20x brighter than ordinary indoor lights.
- Patients either got an 1 and 1/ 2of bright light in the morning, 1 and 1/2 in the evening, or a morning placebo of two deactivated negative-ion generators.
- After 3 weeks, significantly more people in the morning light treatment group than in the placebo group showed significantly more compete on near compete remission of their symptoms.
- The response to evening light was also better than placebo, but not a level of significance.
- Importantly, Eastman’s group found that effective phototherapy fostered full remission of depression.
- 30% of sufferers in the placebo group also seemed to recover.
92
Types of neurones:
- Sensory neurone
- Relay neurone
- Motor neurone
93
Sensory neurone:
- Picks up messages from the outside world through sensory receptors, it uses our 5 senses.
- It carries the electrical impulse from sensory receptors to the CNS.
- Characterisation: long dendrites and short axons.
94
Relay neurone:
- Carries info across the spinal cord/brain from sensory nerves to motor neurones.
- Based in the brain.
- Characterisation: short dendrites and short axons.
95
Motor neurone:
- Repsonible for controlling muscles.
- Carries impulses from CNS to effector e.g: muscles/glands.
- Characterisation: short dendrites and long axons.
96
What are neurotransmitters:
- They allow the transfer of signalling messages between brain cells.
- Neurotransmitters are located in a part of the neurone called the axon terminal. They’re stored within
97
Excitory NT:
Likely to fire and continue.
98
Inhibitory NT:
Less likely to continue, won’t fire.
