Biopsychology

Question 1

Nervous System

Answer 1

The nervous system is divided into the two main components:
1) the central nervous system (CNS) 2) the peripheral nervous system (PNS).
The nervous system is a network of nerves cells that transmit messages between different parts of the body, allowing communication to take place.

Question 2

Central nervous system

Answer 2

The CNS consists of the brain and the spinal cord. The brain provides conscious awareness and is involved in all psychological processes.
- The brain stem connects the brain and spinal cord and controls involuntary processes,including our heartbeat, breathing and consciousness.
- The occipital lobe processes visual information
- The temporal lobe processes auditory information
- The parietal lobe integrates information from the different senses and therefore plays an important role in spatial navigation
- The frontal lobe is associated with higher-order
functions, including planning, abstract reasoning and logic.

Question 3

Spinal cord

Answer 3

passes messages to and from the brain via the PNS, the peripheral nervous system. It’s also responsible for reflex actions

Question 4

The Peripheral Nervous System

Answer 4

The role of the peripheral nervous system (PNS) is to relay messages (nerve impulses) from the CNS (brain and spinal cord) to the rest of the body.
The PNS consists of two main components:
1) the somatic nervous system
2) the autonomic nervous system.

Question 5

somatic nervous system

Answer 5

The somatic nervous system transmits sensory and motor signals to and from the central nervous system, and therefore, it consists of motor neurons and sensory neurons.

• controls voluntary movements, transmits and receives messages from the senses

Question 6

autonomic nervous system

Answer 6

• maintains internal processes like body temperature, heart rate and blood pressure.
• only consists of motor pathways and has two components:
  1) the sympathetic nervous system 2) the parasympathetic nervous system.

Question 7

The sympathetic nervous system

Answer 7

The sympathetic nervous system is typically involved in responses that prepare the body for fight or flight
-increases heart rate
- pupils dilate /start sweating

Question 8

parasympathetic nervous system

Answer 8

is to relax the body, and return us to
our ‘normal’ resting state. Consequently, the parasympathetic nervous system slows down our heart rate and breathing rate, and reduces our blood pressure.

Question 9

The Endocrine System - Glands

Answer 9

The endocrine system works alongside the nervous system. It is a network of glands across the body that secrete chemical messages called hormones

Question 10

The Endocrine System - Hormones

Answer 10

Hypothalamus- Stimulates and controls the release of hormones from the pituitary gland.

Pituitary Gland (Master Gland) -Anterior adrenocortical trophic hormone (ACTH) which stimulates the adrenal cortex and releases cortisol during the stress response. And releases Posterior – oxytocin = Responsible for uterus contractions during childbirth.

The Pineal Gland - Melatonin which responsible for important biological rhythms, including the sleep-wake
cycle.

Thyroid Gland - Thyroxine = Responsible for regulating metabolism.

Adrenal Gland - Adrenal medulla –
Adrenaline & noradrenaline are the key hormones in the fight or flight
response.
- Adrenal cortex - cortisol = Stimulates the release of glucose to
provide the body with energy, while
suppressing the immune system.

Ovaries (female)- Oestrogen = Controls the regulation of the female
reproductive system, including the
menstrual cycle and pregnancy.

Testes (male) - Testosterone = Responsible for the development of
male sex characteristics during
puberty, while also promoting muscle
growth..

Question 11

neurons

Answer 11

Neurons are the information processing units of the brain responsible for sending, receiving, and transmitting electrochemical signals throughout the body.

Question 12

Sensory neurons
(sometimes referred to as afferent neurons

Answer 12

are nerve cells that carry nerve impulses from sensory receptors toward the central nervous system and brain.
- they carry info from the PNS to the CNS
They have long dendrites and short axons

Question 13

Motor neurons (also referred to as efferent neurons)

Answer 13

are the nerve cells responsible for carrying signals away from the central nervous system towards muscles to cause movement. They release neurotransmitters to trigger responses leading to muscle movement.
They have short dendrites and long axons

Question 14

A relay neuron (also known as an interneuron)

Answer 14

they have short axons and short dendrites
They connect the sensory neurons to the motor neurons
They are based in the CNS and carry signals/messages across this part of the nervous system

Question 15

Synaptic transmission is when one neuron communicates to another neuron

Answer 15

• Information is passed down the axon of the neuron as an electrical impulse known as an action potential.
• It must cross over the synaptic gap between the presynaptic neuron and the post-synaptic neuron. At the end of the neuron (in the axon terminal) are **he synaptic vesicles, which contain chemical messengers, known as neurotransmitters.
• When the electrical impulse (action potential) reaches these synaptic vesicles, they release their contents of neurotransmitters.
• Neurotransmitters then carry the signal across the synaptic gap. They bind to receptor sites on the post-synaptic cell, thereby completing the process of synaptic transmission.

Question 16

Electric transmission

Answer 16

Neuron in resting state = negatively charged

Neuron activated by stimulus = positively charged

Positively charged neuron = action potential (electrical impulse from axon to end of neuron)

Question 17

Synaptic transmission

Answer 17

Neurons communicate with each other within groups- neural networks

Neurons separated from each other by tiny gaps called synapse

Signals within neurons transmitted electronically

Signals between neurons are transmitted chemically across the synapse

Question 18

Neurotransmitters
Excitatory/ Excitation

Answer 18

Increases the positive charge of the postsynaptic neuron

This increases the **likelihood that the neuron will fire and pass on the electrical impulse
**
For example- adrenaline (both a hormone and neurotransmitter)

Question 19

Neurotransmitters
Inhibition

Answer 19

Increases the negative charge of the postsynaptic neuron

This decreases the likelihood that the neuron will fire and pass on the electrical impulse

For example- serotonin

Question 20

Summation

Answer 20

Summation: the process which decides whether a post-synaptic neuron fires or not, once it reaches threshold

Excitatory influence + inhibitory influence:
Net effect on post synaptic neuron is inhibitory then the postsynaptic neuron is less likely to fire

Net effect on post synaptic neuron is excitatory it is more likely to f**ire (inside of postively charged postsynaptic neuron)

Question 21

Explain why neurons only transmit information in one direction at a synapse

Answer 21

the synaptic vesicles containing the neurotransmitter are released from the presynaptic membrane
*   the receptors for the neurotransmitters are only present on the postsynaptic membrane
*   it is the binding of the neurotransmitter to the receptor which enables the signal/information to be passed/transmitted on (to the next neuron)
*   diffusion of the neurotransmitters means they can only go from high to low concentration, so can only travel from the presynaptic to the postsynaptic membrane.

Question 22

Explain how anti-depressants/anti-psychotic drugs/drug abuse effects the synaptic transmission

Answer 22

SSRIs such as Prozac, slow down the reuptake of serotonin after it has crossed the synapse ensuring it stays active for longer in the synapse

Question 23

fMRI

Answer 23

Observe brain activity as participants conduct various tasks
Only measures changes in blood flow in particular areas in the brain which indicates increased neural activity
The patient has to stay perfectly still for a clear image

Non- invasive (no radiation used; non-surgical)
causation - No direct measure of neural activity
Spatial resolution - 1-2mm
**Low temporal resolution **- 1-4 secs after activity

Question 24

Post mortems

Answer 24

Detailed examination of the **anatomical and neurochemical aspects of the brain after death **

Invasive- (the person is deceased)
**Informed consent may be difficult to obtain **
Spatial resolution - (Low, changes seen by the eye, not much detail compared to other methods of investigation)
Temporal resolution - (no brain activity- minimal neural changes in the brain after death)

Causation
The patient is on treatment- this could cause changes to the brain **
The abnormal behaviour displayed when the person was alive may not be linked to the brain damage- difficult to establish causation**

Question 25

EEG - Electroencephalogram

Answer 25

An electroencephalogram (EEG) works on the premise that information is processed in the brain as electrical activity in the form of action potentials or nerve impulses, transmitted along neurons. EEG measure this electrical activity through electrodes attached to the scalp. Small electrical charges that are detected by the electrodes are graphed over a period of time, indicating the level of activity in the brain.

Alpha - awake, consciousness
Beta - Relaxed, not thinking
Delta - deep relaxation, mediation
Theta - deep dreamless sleep

Non-invasive - non-surgical procedure (no-radiation)
used in sleep clinic diagnosis

Temporal resolution - it takes readings every millisecond - it can record the brain activity in real life
1-10 ms

Spatial resolution - poor - can only detect the activity in superficial regions of the brain, they are unable to provide information on what is happening in the deeper regions of the brain such as the hypothalamus

Question 26

Event-Related Potentials (ERP)

Answer 26

Event-Related Potentials (ERP) use similar equipment to EEG, electrodes attached to the scalp. However, the key difference is that a stimulus is presented to a participant (for example a picture/sound) and the researcher looks for activity related to that stimulus.

sensory ERPs - Waves (responses) that occur within 100 milliseconds following the presentation of a stimulus
cognitive ERPs - ERPs that occur after 100 milliseconds, they demonstrate some information processing.

Non-invasive - non-surgical procedure (no-radiation)
used in sleep clinic diagnosis

Temporal resolution - it takes readings every millisecond - it can record the brain activity in real life
1-10 ms

Spatial resolution - poor - can only detect the activity in superficial regions of the brain, they are unable to provide information on what is happening in the deeper regions of the brain such as the hypothalamus

Question 27

Localisation of Function

Answer 27

Different areas of the brain are responsible for different behaviours, processes and activities. If different areas of the brain become damaged through illness or injury, the function associated with that area will also be affected.

Question 28

Pierre Flourens
1794-1867

Answer 28

He systematically removed parts of animals’ brains to see what happened to their behaviours.

“i removed the cerebellum in a young but vigorous dog by a series of deeper and deeper slices. The animal lost gradually the faculty of orderly and regular movements. He had all his intellectual faculties …he was only deprived of the faculty of coordinating and regularising his movements”

Question 29

Paul Broca’s
1824-1880

Answer 29

A patient ‘Tan’ had difficulty in producing speech when tan died. Broca performed a post-mortem on him and found out that his frontal lobe was damaged.

Question 30

Wernicke’s
1848-1905

Answer 30

Wernicke’s patients had problems understanding language. An area of the temporal lobe was damaged. Damage to Wernicke’s produces difficulty in understanding spoken /written language. The language that they produced is muddled. They often produce neologisms, new words, expressions and meanings of words.

Question 31

Phineus Gage 1848

Answer 31

had a hole in his head. Damage to his frontal lobe could alter aspects of personality and affect social skills

Question 32

Motor cortex

Answer 32

Where - at the **back of the frontal lobe in both hemispheres **
What - this controls voluntary movement on the opposite side of the body. Damage to this area of the brain may result in a loss of control over fine movements

Question 33

Somatosensory cortex

Answer 33

Where - At the front of the parietal lobes is the somatosensory area which is separated from the motor area by a valley called the central sulcus.
What - where sensory information from the skin (e.g touch, heat, pressure, etc) is represented. The amount of somatosensory area devoted to a particular body part denotes it’s sensitivity, receptors for our face and hands occupy over half of the somatosensory area.

Question 34

Visual cortex

Answer 34

Where - in the occipital lobe at the back of the brain **
What - Each eye sends information from the right visual field to the left visual cortex and from the left visual field to the right visual cortex**. This means that damage to the left hemisphere, for eg can produce blindness in part of the right visual field of both eyes.

Question 35

Auditory cortex

Answer 35

Where- the temporal lobes house of the auditory area
What - Which analyses speech-based information. Damage may produce partial hearing loss. The more extensive the damage, the more extensive the loss. In addition, damage to a specific area of the temporal lobe Wernicke’s area - may affect the ability to comprehend language.

Question 36

Lateralisation theory

Answer 36

Lateralisation is the idea that the two halves of the brain are functionally different and that each hemisphere has functional specialisations, e.g. the left is dominant for language, and the right excels at visual motor tasks.

Question 37

Corpus callosum

Answer 37

The two hemispheres are connected through nerve fibres called the corpus callosum, which facilitate interhemispheric communication: allowing the left and right hemispheres to ‘talk to’ one another.

Question 38

Sperry’s spilt brain research

Answer 38

Aim: The aim of their research was to examine the extent to which the two hemispheres are specialised for certain functions and the effects of hemisphere disconnection

IV - whether the individual had a split brain or not
DV - Individual’s performance on visual/tactile test/Drawing test/describe what you see
research method - quasi-experiment in a laboratory with independent group design.

findings -
When a picture was shown to the right visual field, the patient could describe it easily. When the image was shown to the left visual field, the patient found it difficult to describe it, or couldn’t see anything there.
- The left hand was much better at drawing images than the right hand, despite the fact that all of the patients tested were right-handed. This shows that the right hemisphere seems to be dominant for drawing skills.
conclusions
People with split brains have two separate visual inner worlds, each with its own train of visual images.
Split-brain patients have a lack of cross-integration where the second hemisphere does not know what the first hemisphere has been doing.
Split-brain patients seem to have two independent streams of consciousness, each with its own memories, perceptions and impulses ie two minds in one body

Question 39

Some researchers propose that it is not so much that various functions are lateralised but that each hemisphere processes information differently

Answer 39

Bradshaw and Sherlock 1982 proposed that the difference between the hemispheres is whether they are analytic vs synthetic.

Sperry 1985 proposes that the right hemisphere processes information as a whole (synthetic) whereas the left hemisphere processes information analytically (bit-by-bit).

Question 40

The myth of left brainers and right brainers -reductionist

Answer 40

There is a common belief that people routinely use one hemisphere more than the other. ‘Left-brainers’ are considered to be objective, and good at logic and analysis. Right-brainers are supposed to be creative, and intuitive and use subjective reasoning. While this seems like a good explanation for being better at some subjects than others, it is an oversimplification. The many complex tasks. that we do every day e.g. texting, and reading requires us to use both four brains.
While the hemisphere can do different functions, this is only apparent for very simple tasks. Most of the time, our two hemispheres work together sharing information.

Question 41

Synaptic pruning

Answer 41

as we age rarely used connections are deleted and frequently used connections are strengthened.

Question 42

Brain plasticity

Answer 42

the brain’s ability to change and adapt as a result of experience and new learning. This generally involves the growth of new connections.

Question 43

Brain plasticity supporting evidence 1 - Maguire et al 2000

Answer 43

• studied the brains of London taxi drivers and found more volume of grey matter in the posterior hippocampus than in the control group. Maguire et al found that this learning experience alters the structure of the taxi drivers brain. They found that the longer the taxi drivers had been on the job the more pronounced the structural difference ( a positive correlation)

Question 44

Functional recovery

Answer 44

the brain is able to require and reorganise itself by forming new synaptic connections close to the area of damage.
secondary neural pathways that would not typically be used to carry out certain functions are activated and unmasked to enable functioning to continue in the same way as before. - reformation of blood vessel

Stroke - neurons next to damaged brain sites can take over at least some of the functions that have been lost.

Question 45

Axonal Sprouting

Answer 45

the growth of new nerve endings which connect to other undamaged nerve endings to form new neural pathways.

Question 46

consequences of desynchronisation?

Answer 46

• reduced concentration from 6am
• Poor health - more likely to get heart attacks/ cardiovascular disease

Question 47

Structural plasticity

Answer 47

experiences or memories change a brain’s physical structure

Question 48

Brain plasticity supporting evidence 2 - Mechelli et al 2004

Answer 48

Bilingual brains have a larger left inferior parietal cortex than monolingual brains.This part of the brain is known to be concerned with language, mathematics and body image.

Question 49

Brain plasticity supporting evidence 3 - Draganski et al 2006)

Answer 49

This study scanned the brains of a group of German medical students 3 months before and right after an important exam.
It then compared the scans to scans of students who were not studying for an exam.

Findings:
The students who were studying for an exam showed learning-induced changes in the parietal cortex and posterior hippocampus, regions known to be involved in memory retrieval and learning

Question 50

biological rhythms

Answer 50

Biological rhythms are cyclical patterns within biological systems that have evolved in response to
environmental influences, e.g. day and night.
There are 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.

Question 51

Circadian Rhythms
24 hours

Answer 51

which regulate a number of body processes such as the sleep/wake cycle and changes in body temperature.

Question 52

Ultradian Rhythms
less than 24 hours

Answer 52

A biological rhythm with a frequency of more than one cycle in 24 hours, such as the stages of sleep. (the sleep cycle)

Question 53

Infradian Rhythms
more than 24 hours

Answer 53

a type of biological rhythm with a frequency of less than one cycle in 24 hours such as menstruation and seasonal affective disorder.

Question 54

Endogenous pacemakers

Answer 54

internal body clock that regulates many of our biological rhythms, such as the influence of SCN on the sleep/wake cycle.

Question 55

Exogenous zeitgebers

Answer 55

External cues that affect or entrain our biological rhythms, such as the influence of light on the sleep/wake cycle.

Question 56

Michel Siffre

Answer 56

Aim - Siffre wanted to find out what his natural sleep-wake cycle would be without any zeitgebers.

Method - He took a supply of frozen food and 780 gallons of water into the cave. When Siffre woke up and thought it was daytime, he phoned the research team above ground and they switched on the lights in the cave. He conducted daily experiments on his blood pressure, , memory and physical tests.

Findings - His condition was so dire that Siffre thought of suicide. His STM, mental health and eyesight all got worse. He believed the date was a month earlier than it was. This suggests that his 24 hour clock was increased by the lack of external cues, making him believe one day was longer than it was. This led to his thinking that fewer days passed.

Conclusion - Circadian rhythms persist despite isolation from natural light, which demonstrates the existence of an ‘endogenous clock’
External cues are important because the clock was not accurate, it varied from day to day.

Question 57

Aschoff and Wever (1976)

Answer 57

AIM - found that participants who spent 4 weeks in a bunker

Findings - 1 participant’s sleep-wake cycle was extended to 29 hours. Displayed a circadian rhythm between 24 - 25 hours.

Conclusion - Siffre and the bunker study suggests that the natural sleep-wake cycle may be slightly longer than 24 hours but that it is entrained by exogenous zeitgebers associated with our 24-hour day (such as the no. daylight hours, and typical meal times)
This suggests the natural circadian rhythm is slightly shortened by the effects of daylight.

Question 58

Biological rhythums= Circadian Rhythms - Practical application

Answer 58

Consequences of desynchronization - Duffy et al 2001 found that ‘morning people’ prefer to rise and go to bed earlier (6 am- 10 pm). Whereas evening people prefer to wake and go to bed later (10am to 1pm)

Hormones - Hormones like melatonin and cortisol may increase or decrease as part of your circadian rhythm. Melatonin is a hormone that makes you sleep, and your body releases more of it at night and suppresses it during the day. Cortisol can make you more alert, and your body produces more of it in the morning

Chronotherapeutics - Dobson 1999 refers to the importance of the specific time patients take medication, as this has a significant impact on success.

Pharmacokinetics- Action of drugson the body and how well they are absorbed and distributed. They are certain times during the day nad night time when drugs are more effective.

Question 59

McCintock 1998

Answer 59

Aim - Studied 29 women with irregular periods.

Methods - A sample of pheromones was gathered from nine women at different stages of their menstrual cycles, in a cotton pad placed in their armpit. The pads were worn for at least 8 hours to ensure that pheromones were picked up. The pads were treated with alcohol and frozen, to be rubbed on the upper lip of other participants.

Findings - 68% of the rubbed-lip women began to synchronise with the odour donor.

Question 60

Seasonal Affective Disorder

Answer 60

Is a depressive disorder which has a seasonal pattern of onset, and is described and diagnosed as a mental disorder in DSM-S.

• Circannual rhythm governed by a yearly cycle (winter)

Symptoms - Persistent low mood, lack of general activity and interest in life.

Onset - triggered during the winter months when the no. of daylight hours becomes shorter.

Treatment - a light box which stimulates very strong light to reset the body’s internal clock. Lightbox is preferred over antidepressants to treat SAD as it’s regarded as safe. Light therapy can produce headaches and eye strain. Kelly Rohan et al 2009 recorded a relapse rate of 46% over successive winters, compared to 27% in the comparison group receiving CBT.

Explanation - Psychologists have hypothesised that the hormone melatonin is implicated in the cause of SAD. During the night the pineal gland secretes melatonin until dawn when there is an increase in light. During winter, the lack of light in the morning means this secretion process continues for longer. This is thought to have a knock-on effect on the production of serotonin in the brain - a chemical that has been linked to the onset of depressive symptoms.

• However, it is important to note that Eastman et al 1998 recorded a placebo effect in 30 Ps ( a fake negative generator was used and Ps were told this was another form of treatment.

Question 61

Explain how SAD is another example of an Infradian rhythm

Answer 61

SAD is a particular type of infradian rhythm called a circannual rhythms as the experience of SAD may be due to the disruption of the sleep/wake cycle and this can be prolonged periods of daily darkness during winter.

Question 62

Ultradian Rhythms

Answer 62

a cycle that continues throughout the course of the night. Each of these stages is characterised by a different level of brainwave activity which can be monitored by an EGG.

Question 63

Stages of sleep
On average from 4 to 5 cycles
Happens more then a once every 24 hours

Answer 63

Stages 1 and 2 - this is **light sleep **where a person may be easily woken.In stage 1, brain waves are high frequency and have a short amplitude. These are alpha waves. In stage 2, the alpha waves continue but there are occasional random changes in pattern called sleep spindles

Stage 3 and 4 - this is known as** deep sleep or slow wave sleep**. The brain waves are delta waves with lower frequency and higher amplitude. It is difficult to wake someone at this point.

Stage 5 (REM SLEEP) the body is paralysed yet brain activity closely resembles that of the awake brain. During this time, the brain produces theta waves and the eyes move around, thus rapid eye movement (REM). Dreams are most often experienced during REM sleep, but may also occur in deep sleep.

Question 64

Endogenous pacemakers

Answer 64

Internal body clocks that regulate many of our biological rhythms, such as the influence of suprachiasmatic nucleus (SCN) on the sleep/wake cycle.

Question 65

Exogenous zeitgebers

Answer 65

External factors that affect or entrain our biological rhythms, such as the influence of light on the sleep/ wake cycle

Question 66

Suprachiasmatic nucleus (SCN)

Answer 66

• controls the **production of melatonin **
  It is tiny bundle of nerve cells located in the hypothalamus in each hemisphere of the brain. It is one of the primary endogenous pacemakers. The SCN lies just above the optic chiasm. It receives information about light directly from this structure. This continues even when our eyes are closed enabling the biological clock to adjust to changing patterns of daylight whilst we are sleep

Question 67

Suprachiasmatic nucleus (SCN) and the sleep cycle 2
SCN have a nerve input directly from the retina of the eye, so they are kept informed about the zeitgebers of light and darkness even when our eyes are closed

Answer 67

SLEEP
In darkness this information is transmitted to the pineal gland which manufactures melatonin a hormone which stimulates the production of serotonin in the raphe nucleus

Serotonin reduces levels of arousal and so induces sleep

Question 68

SCN and the sleep cycle
Awake

Answer 68

1. SCN have a nerve input directly from the retina of the eye, so they are kept informed about the zeitgebers of light and darkness when our eyes are closed.
2. When light enters through the eyes it stimulates the SCN to produce inhibitors
3. This inhibits the production of melatonin by the pineal gland and so maintains arousal levels - keeping you alert and awake

Question 69

Morgan 1955

Answer 69

Aim - bred hamsters so that they had circadian rhythms of 20 hours rather than 24 hours

Methods - SCN neurons from these abnormal hamsters were transplanted into the brains of normal hamsters, which displayed the same abnormal circadian rhythm of 20 hours showing that the transplanted SCN had imposed its patterns into the hamsters.

Conclusion- this research demonstrates the significance of the SCN and how endogenous pacemakers are important for biological circadian rhythms

Question 70

Exogenous zeitgebers
Light

Answer 70

Light
It can reset the body’s main endogenous pacemaker, the SCN.
Light has an indirect influence on key processes in the body that control such functions as hormones secretion and blood circulation.

Campbell and Murphy 1998 demonstrated that light may be detected by skin receptor sites on the body even when the same information is not received by the eyes. This suggests that light is a powerful exogenous zeitgeber that need not necessarily rely on the eyes to exert its influence on the brain

Question 71

Exogenous zeitgebers
Social cues

Answer 71

Newborn babies initial sleep/wake cycle is random. At about 6 weeks of age, the circadian rhythms begin and by about 16 weeks, babies rhythms have been entrained by the schedules imposed by parents, including adult-determined mealtimes and bedtimes.

Research on jet lag suggests that adapting to local times for eating and sleeping (rather than responding to one’s own feelings of hunger and fatigue) is an effective way of entraining circadian rhythms and beating jet lags when travelling long distances

Question 72

Ultradian Rhythms- The sleep cycle Dement and Kleitman (1957)

Answer 72

Monitored the sleep pattern or g Ps in a sleep lab
Brainwave activity was recorded on an EEG and the researchers controlled the effects of caftine and alcohol.

Findings:
REM activity during sleep was highly correlated with how vivid dreams were and Ps woken up during dreaming reported very accurate recall of their dreams

Conclusion - REM sleep is an important component of the Ultradian sleep cycle

AO3 point - supporting evidence adds credibility to the ultradian rhythms sleep cycle
- furthers our understanding into sleep cycle/ sleeping and possibly leading to effective treatment.

Question 73

Ultradian Rhythms- The sleep cycle
Kleitman 1969

Answer 73

BRAC (Basic rest activity cycle)- 90 mins cycle
continues during the day when we are awake
• State of alertness state of physiological fatigue

Human mind can focus for 90 mins- towards the end of 90 mins the body begins to run out of resources, lack of concentration, fatigue and hunger

Question 74

Ultradian Rhythms- The sleep cycle
Ericsson et al (2005)

Answer 74

Studied group of elite violinists and found that practice sessions were usually limited to a duration of no longer than
90 min at a time.
Fatigue was at the end of the BRAC cycle
Violinist napped to recover from practice
Same pattern among other musician, athletes, chess players and writers