6. A2 - Biopsychology Flashcards

1
Q

Define - Localisation of Function

A

certain functions have certain locations within the brain.

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2
Q

Define - Hemispheric Lateralisation

A

two halves of the brain are functionally different and each
hemisphere has functional specialisations

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3
Q

What is the motor area?

A

voluntary movements by sending signals to the muscles in the
body.

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4
Q

What is the somatosensory area?

A

receives incoming sensory information from the skin to produce sensations related to pressure, pain, temperature, etc.

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5
Q

What is the visual area?

A

receives and processes visual information.

contains different parts that process different types of information including colour, shape or movement.

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6
Q

What is the auditory area?

A

analysing and processing acoustic information.

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7
Q

What is the Broca area?

A

left frontal lobe

language production.

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8
Q

What is the wernickes area?

A

left temporal lobe

language processing/comprehension.

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9
Q

What is Split-Brain Research?

A

Corpus callosum is cut.

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10
Q

What is Plasticity?

A

brain’s ability to change and adapt because of experience.

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11
Q

What is functional recovery?

A

transfer of functions from a damaged area of the brain after trauma to other undamaged areas.

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12
Q

Give an example of a case study for localisation of function

A

Phineas Gage,

  • rail line
  • piece of iron through his skull.
  • experienced a change in personalities, such as loss of inhibition and anger.
  • evidence for localisation of brain function
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13
Q

Where is the motor area located?

A

Frontal lobe

voluntary movements by sending signals to the muscles in the body.

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14
Q

What did Hitzig and Fritsch discover?

A

Different muscles are coordinated by different areas of the motor cortex by electrically stimulating the motor area of dogs.

This resulted in muscular contractions in different areas of the body depending on where the probe was inserted.

The regions of the motor area are arranged in a logical order eg. finger next to hand.

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15
Q

Where is the somatosensory area?

A

In the parietal lobe

Receives incoming sensory information from the skin to produce sensations related to pressure, pain, temperature etc.

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16
Q

What did Robertson discover?

A

The somatosensory area of the brain is highly adaptable

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17
Q

Where is the visual area?

A

back of the brain in the occipital lobe

Receives and processes visual information.

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18
Q

How does the visual area work?

A

right to left and left to right.

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19
Q

Where is the auditory area located?

A

Temporal lobe

Responsible for analysing and processing acoustic information.

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20
Q

How does the auditory area work?

A

left to right and right to left

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21
Q

Who is the Broca’s area named after?

A

Paul Broca

  • Tan - understand spoken language not to produce any coherent words
  • After death - post-mortem examination lesion in the left frontal lobe.
  • conclude area was responsible for speech
    production.
  • Broca’s aphasia, which results in slow and inarticulate speech.
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22
Q

Explain the story of how the Broca’s area was discovered

A
  • Treating a patient named Leborgne, who was more commonly referred to as ‘Tan’.
  • Tan could understand spoken language but was unable to produce any coherent words, and could only say ‘Tan’.
  • After Tan’s death, Broca conducted a post-mortem examination on Tan’s brain and discovered that he had a lesion in the left frontal lobe.
  • This led Broca to conclude that this area was responsible for speech production.
  • People with damage to this area experience Broca’s aphasia, which results in slow and inarticulate speech.
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23
Q

Who discovered the Wernicke’s area?

A

Carl Wernicke’s.

Understanding language.

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24
Q

How was the Wernicke’s area discovered?

A
  • lesions - able to speak, - unable to comprehend language.
  • left temporal lobe - language processing/comprehension.
  • Wernicke’s aphasia - producing sentences that are fluent, but meaningless
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25
What did Wernicke conclude?
Language involves a separate motor and sensory region. The motor region is located in the Broca's area and the sensory in the Wernicke's area.
26
What connected the two hemispheres in the brain?
Corpus callosum Facilitate interhemispheric communication allowing the left and right hemispheres to talk to one another.
27
What does the corpus callosum do?
Facilitate interhemispheric communication allowing the left and right hemispheres to talk to one another.
28
Who did the split-brain research?
Sperry and Gazzaniga (1967)
29
what was the aim of the split-brain research?
Examine the extent to which the two hemispheres are specialised for certain functions.
30
What method was used during the split-brain research?
* image/word projected to the patient’s left visual field or the right visual field. * information presented to one hemisphere can not be transferred to other hemi. Sperry and Gazzaniga diff tasks, tactile tests, and drawing tasks. * **describe what you see** * **tactile test,** object placed in the patient’s left or right hand and they had to either describe what they felt or select a similar object from a series of alternate objects. * **drawing task** picture in either left or right visual field they simply draw what they saw.
31
What were the findings of the **describe what you see** task of the split-brain experiments?
32
What were the findings of the **tactile tests** of the split-brain experiments?
33
What were the findings of the **Drawing tasks** of the split-brain experiments?
34
What conclusions were made from the split-brain research?
key differences between hemispheres. * left hemisphere is dominant in terms of speech and language. * right hemisphere is dominant in terms of visual-motor tasks.
35
What is functional recovery?
transfer of functions damaged area of the brain after trauma to other undamaged areas. - Done through neural unmasking.
36
What is neuronal unmasking?
Way of functional recovery. Where dormant synapses open connections to compensate for a nearby damaged area of the brain. Allows new connections in the brain to be activated thus recovering any damage occurring in specific regions.
37
What did Kuhn et al. discover about plasticity and functional recovery?
* increase in grey matter after participants played video games for 30 minutes a day over a two-month period.
38
What did Davidson et al. discover about plasticity and functional recovery?
* Demonstrated the permanent change in the brain generated by prolonged meditation * **Buddhist monks -** meditated frequently - greater activation of gamma waves * **students -** no experience of meditation. * highlight the idea of plasticity and the brain’s ability to adapt as a result of new experience
39
What does fMRI stand for?
Functional magnetic resonance imaging
40
what does a functional magnetic resonance imaging machine do?
* brain-scanning technique that measures blood flow in the brain when a person performs a task. * most active neurons = most energy used. * creates a dynamic (moving) 3D map of the brain * highlighting which areas are involved in different neural activities.
41
What does EEGs stand for?
Electroencephalogram
42
What does a Electroencephalogram do?
* premise that information is processed in the brain as electrical activity in the form of action potentials or nerve impulses, transmitted along neurons. * measure electrical activity through electrodes attached to the scalp. * Small electrical charges are detected by the electrodes are graphed over a period of time, indicating the level of activity in the brain.
43
What does Event-Related Potentials do?
* similar equipment to EEG * key difference is that a stimulus is presented to a participant and the researcher looks for activity related to that stimulus.
44
What does ERPs stand for?
Event-Related Potentials
45
What is a post-mortem examination?
* study the physical brain of a person who displayed a particular behaviour while they were alive that suggested possible brain damage.
46
What does studying of the brain allow?
allows psychologists to gain important insights into the underlying foundations of our behaviour and mental processes.
47
How do fMRI machines work?
* brain-scanning technique that measures blood flow in the brain when a person performs a task. * premise that neurons in the brain that are the most active during a task use the most energy. * Deoxygenated haemoglobin has a different magnetic quality from oxygenated haemoglobin. * 3D image highlights different magnetic qualities. * 1-4 seconds after it occurs and accurate within 1-2 mm. * increase in blood flow response to the need for more oxygen
48
How do EEG machines work?
* information releases electrical activity as action potentials or nerve impulses * Electrodes detect small electrical charges and can be graphed
49
What patterns do EEGs include?
Alpha waves beta waves theta waves delta waves
50
What two distinctive states do EEG patterns produce?
synchronised and desynchronized patterns. A synchronised pattern is where a recognised waveform (alpha, beta, delta and theta) can be detected, whereas a desynchronized is where no pattern can be detected.
51
What can EEGs be used for?
To detect illnesses like epilepsy and sleep disorders and Alzheimer's diseases.
52
How do ERPs work?
* electrodes attached to the scalp. * participant presented with stimulus and researcher looks for activity * stimulus is present many times and average response is graphed - called 'averaging' * latency - time or interval between presentation of the stimulus and the response * Waves occur within 100 milliseconds following the presentation of a stimulus - sensory ERPs - reflect sensory response to the stimulus ERPs
53
What is a latency?
The time or interval between the presentation of the stimulus and the response is referred to as latency. ERPs have a very short latency
54
Explain how EEGs and ERPs are non-invasive
* do not use radiation or inserting instruments directly into the brain and are therefore virtually risk-free. * cheaper techniques in comparison with fMRI scanning and are therefore more readily available. * allows more patients/participants to undertake could help psychologists to gather further data on the functioning human brain + develop understanding of different psychological phenomena eg Alzheimer's.
55
Explain how EEGs and ERPs have poor spatial resolution
* only detect the activity in superficial regions of the brain. * unable to provide information on what is happening in the deeper regions of the brain * technique limited in comparison to the fMRI, * spatial resolution of 1-2mm.
56
Explain how EEGs and ERPs have a good temporal resolution
* takes readings every millisecond * record the brain’s activity in real-time * accurate measurement of electrical activity when undertaking a specific task. * uncomfortable for the participant, as electrodes are attached to the scalp. * result in unrepresentative readings as the patient’s discomfort may be affecting cognitive responses to situations. * fMRI scans - less invasive and not cause discomfort, more accurate recordings.
57
Explain why EEGs can not pinpoint the exact region of activity.
* electrical activity is often detected in several regions of the brain simultaneously. * difficult pinpoint exact area/region of activity, * difficult for researchers to draw accurate conclusions.
58
Explain why ERPs are more experimentally robust
* enable determination of processing is affected by a specific experimental manipulation. * more experimentally robust * eliminate extraneous neutral activity, * scanning techniques (and EEG) may struggle to do.
59
Explain how a post-mortem examination works
* study the physical brain of a person who displayed a particular behaviour while they were alive that suggested possible brain damage. * Iverson - schizophrenic patients - link to dopamine * post-mortem studies allow for a more detailed examination of anatomical and neurochemical
60
Give an example of a disorder that has been further understood due to Post-Mortem examinations
schizophrenic - higher concentration of dopamine
61
What do post-mortem studies allow?
A more detailed examination of **anatomical** and **neurochemical** aspects of the brain.
62
What is a biological rhythm?
* cyclical patterns within biological systems * evolved in response to environmental influences, * two key factors that govern biological rhythms: **endogenous pacemakers (internal)**, the body’s biological clocks, and **exogenous zeitgebers (external)**, which are changes in the environment.
63
What is a circadian rhythm?
One biological rhythm is the **24-hour** circadian rhythm (often known as the ‘body clock’), which is **reset by levels of light**. The word circadian is from the Latin ‘circa’ which means ‘about’, and ‘dian’, which means ‘day’. Examples of circadian rhythms include the **sleep- wave cycle and body temperature.**
64
What is an infradian rhythm?
* biological rhythm * **last longer than 24 hours** * female menstrual cycle * regulated by hormones either promote ovulation or stimulate the uterus for fertilisation.
65
What is an ultradian rhythm?
* **less than 24 hours** * human sleep. * alternates between REM and NREM sleep and consists of five stages. * starts at light sleep + progressing to deep sleep and then into REM sleep dreaming occurs * repeats every 90 minutes throughout the night about five complete sleep cycles each night.
66
What is an endogenous pacemaker?
* **Endogenous pacemakers - internal** * biological rhythms + circadian sleep/wake cycle. * biological clocks * altered and affected by the environment. * The most important endogenous pacemaker is the **suprachiasmatic nucleus,** * closely linked to pineal gland * both influential in maintaining the circadian sleep-wake cycle.
67
What is an exogenous zeitgeber?
* biological rhythms * environmental events that are responsible for resetting the biological clock * social cues like meal times and social activities, * most important is light, * responsible for resetting the body clock each day, keeping it on a 24-hour cycle.
68
What are the two key factors that govern biological rhythms?
* **endogenous pacemakers** (internal factors), the body’s biological clocks * **exogenous zeitgebers** (external factors), which are changes in the environment.
69
How long does a circadian rhythm last?
24 hours reset by levels of light
70
What are two examples of circadian rhythm?
* sleep-wake cycle * body temperature
71
Explain the sleep-wake cycle as an example of a circadian rhythm
* Light = primary input = external cue for sleeping or waking. * detected by the eye = sends messages concerning level of brightness to the suprachiasmatic nuclei (SCN). * SCN uses information to coordinate the activity of the entire circadian system. * Also works with homoeostasis. * when awake a long time, homeostasis tells the body to sleep because of energy consumption. * This drive for sleep increases throughout the day, reaching its maximum in the late evening when most people fall asleep.
72
How does body temperature work as a circadian rhythm?
* temp lowest in the early hours of the morning (36oC at 4:30 am) * highest in the early evening (38oC at 6 pm). * Sleep occurs when core temperature starts to drop * body temperature starts to rise at end of a sleep cycle * promoting feelings of alertness
73
Give issues and debates on research support for circadian rhythms
* Siffre’s case study criticised. * **generalisability**. * Aschoff & Weber additional support - participants living in a bunker. - no windows - only artificial light - 25-27 hours cycle * natural light (exogenous zeitgebers) to regulate a 24-hour circadian sleep-wake cycle, demonstrating the importance of light for this circadian rhythm.
74
How are biological rhythms regulated?
Endogenous pacemakers Body's internal biological clocks
75
What helps to regulate internal biological clocks?
Exogenous zeitgebers external cues
76
How does the environment and endogenous pacemakers interact?
can be altered and affected by the environment. Siffre - in cave and Aschoff & Weber - 25-27 hours under bunkers
77
Which is the most important endogenous pacemaker?
suprachiasmatic nucleus,
78
What is the suprachiasmatic nucleus?
Most important endogenous pacemaker. - Master Clock. Closely linked to the pineal gland, both of which are influential in maintaining the circadian sleep/wake cycle.
79
Where is the suprachiasmatic nucleus found?
In the hippocampus.
80
How does the SCN and pineal gland interact?
* SNC sends signals to the pineal gland * increase in the production of melatonin at night * The SCN and pineal glands work together as endogenous pacemakers * activity is responsive to the external cue of light.
81
What are the two types of exogenous zeitgebers?
* **social cues** such as meal times and social activities * **light**, which is responsible for resetting the body clock each day, keeping it on a 24-hour cycle.
82
What does the SNC contain that links it to the exogenous zeitgebers?
* The SNC contains light sensative receptors * external cue used to synchronise body’s internal organs and glands. * Melanopsin - eye protein - sensitive to light and carries signals to the SCN to set the 24-hour daily body cycle. * social cues - eg. mealtimes - act as zeitgebers and humans can compensate for the lack of natural light, by using social cues instead.
83
Give issues and debates related to the importance of the SCN through research.
* **hamsters**. * respond differently to manipulations of their biological rhythms, * vast differences between environmental contexts. * makes research carried out on other animals unable to explain the role of endogenous pacemakers in the biological processes of humans.
84
How long do infradian rhythms last?
Longer than 24 hours and can be weekly, monthly or annually.
85
What is an example of infradian rhythms?
female menstrual cycle. Seasonal variations in mood.
86
Explain female menstrual cycles in terms of an infradian rhythm
* Ovulation halfway through the cycle when oestrogen levels highest - last 16-32 hours. * After the ovulatory phase - progesterone levels increase in preparation * 28 days but variation
87
Explain seasonal variations in mood.
* Research found seasonal variation in mood, * seasonal affective disorder (SAD) - depressed in winter * infradian rhythm governed by a yearly cycle. * melatonin - responsible. * lack of light during the winter months - longer period of melatonin secretion - linked to the depressive symptoms.
88
Give issues and debates on research linking exogenous zeitgebers and infradian rhythms
* synchronised menstrual cycle * provides evolutionary advantage for groups of women * synchronisation of pregnancies means childcare can be shared among multiple mothers who have children at the same time.
89
How long do ultradian rhythms last?
Fewer than 24 hours and can be found in the pattern of human sleep.
90
What type of scanning technique was used to highlight distinct brain waves during the different stages of sleep?
EEG
91
Explain in terms of brain waves the 5 stages of sleep.
1. **Stages 1 and 2** **are ‘light sleep**’ stages. During these stages brainwave patterns become slower and more rhythmic, starting with alpha waves progress to theta waves. 2. **Stages 3 and 4 are ‘deep sleep’** or slow wave sleep stages, where it is difficult to wake someone up. This stage is associated with slower delta waves. 3. Finally, **Stage 5 is REM (or dream) sleep.** Here is the body is paralysed (to stop the person acting out their dream) and brain activity resembles that of an awake person.
92
Which stages of sleep are light sleep stages?
1 and 2
93
What stages of sleep is deep sleep?
3 and 4
94
Which stage of sleep is REM sleep?
5
95
What are two types of ultradian rhythm?
* sleep * appetite or meal patterns
96
What is plasticity?
The ability to change and adapt in response to experience.
97
What are the two types of neuroplasticity?
* **Structural plasticity (growth)** - experience causes a change to brain structure * **Functional plasticity (recovery)** - localised functions move from a damaged region to an undamaged region after injury
98
What are the four stages of stuctural plasticity?
1. Synaptic pruning 2. Neural unmasking 3. Axonal Sprouting 4. Synaptic connection
99
Explain the 1st stage of structural plasticity
Synaptic pruning Axons that aren't used will weaken and eventually be lost
100
Explain the 2nd stage of structural plasticity
Neural Unmasking A hormone; nerve growth factor (NGF) encourages growth
101
Explain the 3rd stage of structural plasticity
Axonal sprouting Chemicals called neurotrophins sustain and encourage growth
102
What chemical is involved in axonal sprouting?
Neurotrophins
103
Explain the 4th stage of structural plasticity
Synaptic Connection The new connection makes its parent network stronger.
104
What are the 4 staged of functional plasticity?
1. Axon Damage 2. Axonal Sprouting 3. Blood vessels re-form (capillaries and glial cells) 4. Recruitment of homologous (similar) areas.
105
Explain the 1st stage of functional plasticity
Axon Damage (Axotomy) Axon is severed by injury (dendrites would just re-grow)
106
Explain the second stage of functional plasticity
**axonal sprouting** new axon/dendrite growth towards target
107
Explain the third stage of functional plasticity
**blood vessels reform (capillaries and glial cells)** 'Glial' cells wrap around capillaries support blood-brain barrier.
108
Explain the fourth stage of functional plasticity
**recruitment of homologous (similar) areas** usually on the opposite hemisphere.
109
What does SCN stand for?
Suprachiasmatic nucleus
110
How do we wake up?
* Light onto photoreceptor in the retina where neurotransmitters are sent to the optic nerve. * If intense - blue light then cortisol is released from the pituitary gland and we wake up * If more faint - red light then melatonin in pineal gland means we continue to sleep.
111
Evaluate research into localisation of function
* Evidence from **case studies** -Damage to Broca’s and Wernicke’s areas in aphasia. - Expressive (Broca’s) aphasia impairs production of language. - **High pop validity - internal validity.** * **conflicting views** - Equipotentially believing basic motor and sensory functions localised by higher mental functions aren’t. - Lashley (1930) - effect of damage determines by extent rather than location. - suffer reduced cognitive functions - **not internally valid.** * **Individual differences** - Cavalier et al. - large variation in patterns of activation across different individuals. - gender difference - Harasty et al. - women have larger Broca’s - **Lack pop validity, gender bias, reductionist.**
112
Evaluate lateralisations
* **Age difference** - change over time due to plasticity. Older brains are less lateralized. - Sperry’s only adults and only taken once. Limiting representativeness of its sample. - **Lack of pop validity, reductionist.** * **brain-damaged sample** - Sperry unethical - showing patients previously unknown defects. - natural studies, findings prompted further epilepsy surgery - preventing many others from experiencing disability. - **Cost-benefit** - controversial - **ecological validity - NHS** * **Increased neural processing capacity** - using one hemisphere to engage - leave other hemispheres free to engage - little empirical evidence show lateralisation confers advantage to the functionality of the brain. - evidence support.
113
Evaluate plasticity and functional recovery
* **Eco validity -** healthcare. - regular mediation change inner workings - Davidson et al. - Tibetan monks much greater activation of gamma waves. - rehabilitation - Jodie Miller - Left learnt to perform - **nature and nurture** - behaviour change biological structures. * **evidence** - Macguire et al. - taxi - structural plasticity increases hippocampal volume - Schneider et al - recovery +tive correlated with years of education. - Ed gave patients a ‘cognitive reserve’ to call on. - **strong external validity** - * **individual differences -** age - older slower - **dementia** - **lack pop validity** as **reductionist**. - **less ecologically valid**
114
Evaluate fMRI
**Pros** * Non-invasive * No radiation * objective/reliable than self-report * Otherwise couldn’t investigate **Cons** * Correlational data only - 3rd variable problem * Measures blood flow and no activity. Not perfect quantitative source * Modern psychology suggests its communication important which cannot be seen in fMRI - yet (connectome)
115
Evaluate EEG
**Pros** * Real-time info of brain activity * In clinical diagnoses * A low-cost option for research **Cons** * Correlational - 3rd variable problem * Only surface area - needs electrodes for deeper areas, unethical/invasive * Not very sensitive - only from large areas
116
Evaluate ERPs
**Pros** * See changes in brain activity in response to stimuli * Can record processing that has no behavioural response - tell when someone is thinking (lie detector test) **Cons** * Correlational - 3rd variable problem * Need very large sample/trials - time-consuming + expensive * Can’t go deeper - only useful for neocortical measurements
117
Evaluate post-mortem examinations
**Pros** * More detail * All regions studied * 52 early understandings (Harrison 2000) **Cons** * Correlational - can never be tested * Confounding variables * Snapshot only - people dead so no follow up or asking for history
118
Evaluate circadian rhythms
* **Research support** - light importance - Hughes -cortisol peaks when awake - three months of darkness pattern changes - extremes of daylight responsible for variations in hormone - other research - no disruption - **not realistic - reductionist** * **Real-life applications in drug treatment.** - Chronotherapeutics (time-release drugs) - specific times - Released at the target area. - Risk of heart attack greatest during the early morning. - **Economic validity** * **Ignores individual differences** - **not generalise.** - Studies - sleep cycle 13-65 hours - also ‘larks’ and ‘owls’ in human samples - regardless of light or social cues. - **deterministic** - small sample allow valid generalisation - Bio reductionism - External factors likely
119
Evaluate ultradian and infradian rhythms
* **Individual differences** - non-biological factors. - Tucker et al - For deep sleep (stages 3+4) differences are partially significant. - biologically determined. - Problem generalising theory * **Research support for BRAC** - 60-minute lesson length in schools - Truck drivers 90-minute max - ecologically valid research * **menstrual cycle influences mate choice.** - Penton-Voate et al - vary across cycle diff preferences. - shown the opposite - no link was made. - Biologically reductionist - No scientific method used.
120
Evaluate endogenous pacemakers
* **Research suppor**t - **internal validity** - hamster transplant study - donor SCN always determined the circadian rhythm - lamps that mimic daylight - determinism - Animal models lack external validity - the artificial environment - lack ecologically valid. * **Real-life applications** - Burgess et al - avoidance of jet lag - exposed to bright light prior to east-west flight. - If continuous light circadian rhythm shifts 2.1 hours - economic and health benefits. - **Ecologically valid.** * **studies on blind people.** - blind able to rely on their circadian rhythm - forming a visual perception. - Skene and Arendt pathway from retinal cells containing melanopsin to the SCN is still intact. - **pop validity** - **no gender bias** - high reliability.