Biological Psychology Flashcards

Question

What are the Animal studies with the SCN?

Answer 1

DeCoursey’s (2000) Chipmunks: - Destroyed the SCN connection of 30 chipmunks - They were then returned to the wild for 80 days - Sleep wake cycle disappeared so by the end of the study most of them had been eaten as they were asleep at the wrong times Ralph’s (1990) Hamsters: - Bred mutant hamsters with a 20 hour sleep wake cycle - When the SCN of the mutant hamsters was transplanted into 24 hour cycle hamsters, the cycle of the normal hamsters changed to 22 hours

Answer 2

- Numerous circadian rhythms which can act independently = Limitation - this suggests that there may be many other complex influences on the sleep/wake cycle, aside from the master clock (the SCN) - Siffre used artificial light which could have reset his biological clock = Limitation - this suggest the more researchers attempt to isolate the influence of internal pacemakers and exogenous zeitgebers = the lower the validity of the research, in everyday life IP and EZ interact - Ethical harm caused to animals during testing = Limitation - whether what we learn from investigations such as these justifies the aversive procedures involved is a matter of debate - People who live in the artic circle (little darkness in winter and light in summer) have similar sleep patterns all year round, despite spending around six months in almost total darkness = Limitation - this suggests that the sleep wake cycle is primarily controlled by endogenous pacemakers that can override environmental changes in light man had rhythm of 24.9 hours, despite exposure to social cues his sleep/wake cycle could not be adjusted, had to take sedatives at night and stimulants in the morning to keep pace with the 24-hour world= Limitation - this suggests that social cues alone are not effective in resetting the biological rhythm

Answer 3

Activity on the right side of the body

Answer 4

Activity on the left side of the body

Answer 5

Front of brain Deals with logic, planning, decision making, emotions, problem solving, impulse control

Answer 6

Top of the head Deals with orientation, recognition, processing sensory information

Answer 7

Side of the head Deals with hearing, processing auditory information, turns words into sounds, damage to area can lead to hearing loss or problems with language comprehension, contains auditory area which analyses speech based information

Answer 8

Back of the head Deals with visual processing - ipsilateral and contralateral (right goes to left side of both eyes and left goes to right side of each eye

Answer 9

Strip down back of frontal lobe in both hemispheres Deals with controlling voluntary movement in opposite side of the body, damage to area may result in a loss of fine motor movements

Answer 10

Strip in the front of both parietal lobes Deals with sensory information from the skin E.g touch, heat, pressure is represented

Answer 11

Main centre of speech production (Left hemisphere) Broca's aphasia = cannot produce fluent speech but can comprehend speech

Answer 12

Main centre of speech comprehension (Left hemisphere) Patients with damage to Wernickes area can produce fluent speech but cannot comprehend speech

Answer 13

The idea that different parts of the brain perform different tasks

Answer 14

- Lashleys rats = removed 10-50% of the brain, then taught them to learn a maze, found no area was was more or less important in ability to learn maze, learning uses every part of the cortex, rather than being confined to a specific area - supports the holistic theory as it shows learning is too complex to put it down to one specific part - higher cognitive function + brain scan evidence showed Broca's area was active during reading, Wernickes area active during listening = high internal validity Also found semantic and episodic memories reside in different parts of the pre-frontal cortex + Phineas Gage - trauma to frontal lobe due to rail road spike through cheek and out of head = became angry and fitful. Supports localisation of function as he could still perform basic functions - movements and speech - Plasticity - functions of area damaged can be recovered by different parts of brain = suggests more holistic approach rather than each part having individual function

Answer 15

The idea that the two halves of the brain are functionally different - certain functions are controlled by one hemisphere

Answer 16

Left - lateralised

Answer 17

Not lateralised but cross wired/contralateral wiring right controls left, left controls right

Answer 18

Vision is not lateralised Contralateral and Ipsilateral (opposite and same sided) each eye gets information from both the right visual field (RVF) and left visual field (LVF) All information in the RVF goes to the left hemisphere and all information from the LVF goes to the right hemisphere

Answer 19

Nobel prize for work 1981 conducted studies on individuals who had undergone the same surgical procedure - a commissurotomy (tissues which connect two sides of brain were cut down the middle) individuals had two separate brains procedure done to control severe epileptic seizures - stops shocks passing between the two hemispheres Allowed Sperry to see the extent to which the two hemispheres were specialised for certain functions

Answer 20

- Image or word projected to patients right visual field and a different one to left visual field - patient fixate on cross in middle of screen - tested procedure on 11 patients who had already had their corpus collosum cut 1. Patients had to describe what they saw = RVF patient could describe as left hemisphere responsible for language, LVF patient said nothing there as they could not describe it 2. Recognition by touch = although they could not say what they saw, they could select the correct object using their left hand (controlled by right hemisphere) from behind a screen Therefore could not verbally identify the word but could still understand what it was using Right hemisphere Could also pick closely matching objects E.g pick ashtray when shown picture of cigarette to LVF

Answer 21

Left hemisphere is verbal, right is non-verbal right hemisphere can process images and match up objects (non-verbally) When shown racy image to LVF person would giggle/blush (emotional reaction) showing that the RH processes emotion even when the person says they saw nothing

Answer 22

+ brain scans (PET) show different areas are active during a visual task = when participants looked at whole picture the RH is more active, but when asked to focus on specific detail the LH was more dominant Shows the LH and RH have different functions even in connected brains + adaptive advantages to split/lateralised brain = Gazzaniga found lateralised chickens could find food whilst watching for predators but normal chickens couldn't Shows it can be an advantage in animals as well as humans + Sperry's work was standardised and scientific = participants given a 'fixation point' to stare at during the task and also the image only flashed up for a tenth of a second, Sperry could make sure it was only being processed by one hemisphere rather than it being share by both This is a strength because it has high internal validity and replicability - Lack of generalisability with Sperry's work = split brain patients are rare (just 11 males tested, small sample size), all had epilepsy so potential underlying damage in brains caused by the shocks, control group were non-epileptic so comparison is different Limitation as it is not representative of normal brains, therefore not generalisable to wider population, ultimately doesn't tell us a lot about hemispheric lateralisation

Answer 23

The brains ability to change and adapt based on experience and new learning

Answer 24

A form of plasticity which occurs after trauma or damage to the brain. The brain can redistribute or transfer functions that are usually performed by the damaged area to other undamaged areas. Healthy brain areas or tissues appear to be able to take over the functions of areas that are destroyed or missing.

Answer 25

Studied brains of taxi drivers using MRI scanners Found they had more matter in their posterior hippocampus than a control group Part of their brain was involved in spatial navigation London cabbies test called 'the knowledge' Longer they had been doing the job = more pronounced structural difference - positive correlation However, does not test the size of their posterior hippocampus before becoming a taxi driver, therefore can't be sure the difference is due to 'the knowledge'. Could have been taxi drivers due to already existing difference

Answer 26

Draganski = imaged brains of medical students 3 months before and after their medical exams and found learning induced changes (larger and more connections) in the posterior hippocampus and parietal cortex Mechelli found a larger parietal cortex in the brains of people who were bi-lingual in comparison to mono-lingual matched controls This shows when we experience learning, out brain adapts and changes as a result of new experiences and new learned content/knowledge - makes new connections

Answer 27

- Measures changes in brain activity while a person performs a task - Does this by measuring changes in blood flow in particular areas of the brain which indicates neural activity in these areas - measures blood flow using radio waves and a magnetic field, - if part of brain is active, there is an increased demand for oxygen in that area - so increased blood flow and delivery of oxygen in the red blood cells - researchers can produce maps showing which areas of the brain are involved in a particular mental activity - The resulting FMRI data can then be used to identify the brain areas where there is a matching pattern of change. As a result of this data it can be conducted that these areas have been activated by the stimulus in question

Answer 28

Jody Had epileptic seizures had surgery, half brain taken out (right side) within in 10 days she could walk again (LH made new connections) slight paralysis in left hand but functions normally

Answer 29

1. FMRI (Functional magnetic resonance imaging) 2. EEG (Electroencephalogram) 3. ERP (Event related potentials) 4. Post Mortem Examinations

Answer 30

1. Brain rewires/reorganises itself by forming new synaptic connections close to the area of damage 2. secondary neural pathways are activated or 'unmasked' that enable functioning to occur similar to before other structural changes in the brain include: 1. Axonal sprouting: Brain grows new nerve endings which connect to form new neural pathways 2. Denervation super sensitivity: axons that do a similar job become aroused to a higher level to compensate for lost ones 3. Recruitment of homologous areas: this is where similar areas on opposite sides of the brain are recruited to perform tasks E.g Broca's area may move to the right

Answer 31

P - Not all plasticity and functional recovery is a good thing. There are sometimes negative consequences to the brain re-wiring itself E - 60-80% of amputees may suffer from phantom limb syndrome - where a person continues to experience sensations in a missing limb E - May be due to cortical reorganisation in the somatosensory cortex that occurs as a result of limb loss L - Can cause lifetime pain/unhappiness and suffering P - Good practical application E - techniques such as physical and movement therapy and electrical stimulation of the brain may help the brain to 'fix itself' E - 'constraint movement therapy' - stroke patients = repeatedly try and use affected part of body E.g lift arm whilst unaffected arm is restrained L - This is a strength because it has positive effects that can help people recover from injuries P - plasticity can occur throughout your whole life time E - Bezzola conducted study on novice golfers = gave people aged 40-60 who had never played golf 40 hours of training and scanned their brains using FMRI scanner both before and after the training E - Found increased motor cortex activity compared to long term golfers L - supports idea of plasticity and shows it is not limited to young developing brains, but that learning and experiences which occur throughout a lifetime can affect the structure of the brain P - There is animal evidence of plasticity and functional recovery E - Hubel and Wiesel sewed one eye of a kitten shut and analysed the brains cortical responses E - The side of the visual cortex associated with the shut eye would process information from the other eye L - This shows us that, at least in animals, inactive brain areas can change and adapt to take on new functions after damage P - The greater your 'cognitive reserve ' the better your brain will recover from brain injury E - study found that the longer brain injury patients had spent in education, the better chance of recovery. 40% of the patients who recovered fully from their brain injury had spent more than 16 years in education. In comparison just 10% of the patients who recovered fully had spent 12 years in education E - This shows that the more the brain is practising plasticity the better it can recover later in life L - Highlights how factors such as education may impact the chances of successful recovery. We can also question whether there might be other factors such as gender, health or activity levels which also impact the likelihood of functional recovery

Answer 32

FMRI: Strengths + unlike other scans (such as PET scans) it doesn’t rely on the use of a radioactive tracer. Therefore, it is risk free and non - invasive. + it produces high resolution images that are accurate to the millimetre so it provides psychologists with a clear image of where functions are located - The machines are expensive (over 1 mill to buy) compared to other imaging techniques - requires equipment and trained experts. Very costly for the NHS to use and run - It requires patient to stay still for a clear image which wouldn’t be easy for patients with some conditions (E.G children, elderly, those with disabilities) - FMRI is an indirect measure of functioning. It is studying blood flow rather than the actual firing of neurones. As such there is a 5 second delay between the neurone firing and activity being detected (due to the time it takes oxygen to reach the brain. This means that what your seeing isn’t quite real time (it has poor temporal resolution.

Answer 33

- measures electrical activity in the brain through electrodes placed on scalp which detect small electrical charges resulting from the activity of brain cells. When electrical signals from the different electrodes are graphed over a period of time, the resulting representation is called an EEG - the data can be used to detect various types of brain disorders or to diagnose other disorders that influence brain activity such as Alzheimers disease - EEG is often used by clinicians as a diagnostic tool to look for unusual patterns of activity which may suggest neurological abnormalities such as tumours

Answer 34

EEG: Strengths + has been extremely useful in investigating a wide range of issues including epilepsy and sleep disorders/patterns +high temporal resolution (as it can detect electrical activity in under one millisecond) - It is a general measure 0 it can only show groups of neurons firing, it is not strong enough to pick up small signals from individual neurons - It does not allow researchers to differentiate when different but adjacent (next to) areas are firing

Answer 35

- Too crude and general in raw form - uses same technique as EEG but presents a stimulus many times - creating a smooth curve of activation by combining the data in a process called statistical averaging - This removes background electrical noise unrelated to the stimulus, all that is left is event related potentials - The waveform's peaks and dips show exactly when cognitive processes in the Brian happen after the stimulus is presented

Answer 36

ERP’s Strengths + more specific than raw EEG readings + ERP’s are derived from EEG data so they also have excellent temporal resolution - Differing procedures have been adopted across different research institutions (not standardised, so it is difficult to compare and replicate the findings of studies using this technique) - To be successful all extraneous interference needs to be eliminated and this is hard to achieve

Answer 37

- used to establish the underlying neurobiology of a particular behaviour - researchers may study a person who displays an interesting behaviour while they're alive that might suggest underlying brain damage - Subsequently, when a person dies, unusual brains are dissected such as brains that suffered trauma, or from individuals with mental illness - researchers can look for abnormalities that might explain that behaviour and which are not found in control individuals - Early example of this was Broca's work with Tan, who displayed speech problems (could only say Tan due to expressive aphasia) - He found that there was damage/a lesion in an area of the frontal lobe after Tan's death - which is now known as the 'Broca's area'; an important area for speech production

Answer 38

Post Mortems: Strengths + vital during the early days of psychology before technology was developed E.G Broca and Wernicke + Post - mortems improve medical knowledge and help generate hypothesis for further study - Cause and effect is a problem - the differences observed in a dead brain may be unrelated to the behavioural symptom a person showed when they were alive. We have to infer causality - Informed consent - some patients lose the ability to consent during their lifetime due to the issues that make them of interest (HM) to but even those that don’t have these issues are problematic because consent is needed from relatives (and needed quickly)