Cognitive processes

Question 1

Information processing

Answer 1

• may enhance insight
• brain imaging shows that the area associated with recent neural learning remains active while we sleep

Question 2

Information processing

Sleep deprivation

Answer 2

Sleep deprivation has been shown to lead to reduced attention and short-term memory, which then influences what gets saved as long-term memories. It also impacts the performance of higher-level cognitive functions such as decision-making and reasoning.

Question 3

Information processing

It was suggested that the different stages of sleep benefit different types of learning and memory

Answer 3

REM sleep - procedural memory
Stage 2 - memory of facts and events
Early non-REM - motor memory
REM sleep - emotional memory, creativity and insight

Question 4

Information processing

Evidence - Mendrick et al (2003)

Answer 4

Mendrick et al (2003) found that participants’ performance in perception tasks were improved after sleeping

Question 5

Information processing

Evidence - Seehagen (2015)

Answer 5

Seehagen (2015) found that when babies learn a new action, those who take a nap right after show better recall than those who don’t

Question 6

Information processing

Information consolidation theory

Answer 6

• based on cognitive research and suggests that people sleep in order to process information that has been acquired during the day
• argues that sleep allows the brain to prepare for the day to come

Question 7

Information processing

Cognitive process

Answer 7

• sleep is about increasing your consolidation of memory, processing new information and remaining alert enough to learn efficiently
• quantity and quality of sleep have a profound impact on learning and memory

research suggest that sleep helps in two distinct ways
- a sleep-deprived person cannot focus attention optimally and therefore cannot learn efficiently
- sleep itself has a role in the consolidaton of memory, which is essential for processing new information

Question 8

Information processing

Acquisition
Consolidation
Recall

Answer 8

acquisition - the introduction of new information into the brain

consolidation - the processes by which a memory becomes stable and permanent

recall - the ability to access the information, whether consciously or unconsciously after it has been stored

acquisition and recall occur only when we are awake, but research suggests that memory consolidation takes place during sleep through the strengthening of the neural connections that form our memories

Question 9

Information processing

Benefits

Answer 9

Wagner et al (2004) - challenging maths problems are easier understood after sleeping

Gais et al (2006) - retention of new foreign words is better after sleeping

Question 10

Information processing

Karni et al (1994)

Answer 10

method - trained participants on a perceptual speed task

results
- response times did not improve with practise
- after a nights sleep, they performed the task faster

Question 11

Information processing

Schemas

Answer 11

allows us to organise, store and retrieve information efficiently within our minds

However, information that does not fit with our own schema is often forgotten or distorted until it fits

Question 12

Information processing

Smith (1999)

Answer 12

method
- trained in two drawing tasks
- one simple and one more complex
- half of the participants were denied SWS and the other half REM sleep, the night following the training

results
- SWS deprivation only affected the simple task
- REM deprivation only affected the complex task

Question 13

Information processing

Concept of schemas

Answer 13

useful when explaining the cognitive processes taking place during sleep.

During memory consolidation, similar memories seem to reactivate in a pattern, suggesting they are linked in the brain

Question 14

Crick & Mitchison’s (1986) reorganisational theory (dreams)

Reverse learning

Answer 14

the theory is based on the idea of reverse learning which means that memories can be unravelled and destroyed during REM sleep.

During the day, the cortex becomes overloaded with information. During REM sleep, unwanted memories are deleted in order to improve organisation and make safe

Question 15

Reorganisation theory of dreams

Adaptive and parastic memory

Answer 15

adaptive - useful to retain, such as a new skill or relevant information

parastic - useless memories that waste resources

REM sleep prevents parastic memories from forming or destroying those which have already formed. During REM, the brain’s major connections to the ‘outside world’ are switched off. The brain stem (medulla) then sends random but poweful stimuli to the cortex, which gradually weaken neural connections in the brain.

Question 16

Parastic memories

Answer 16

Crick & Mitichison suggest that as these parastic memories are being unravelled, a random selection of thoughts and memories form themselves into a dream.

Question 17

Crick & Mitichison’s Reorganisational theory

Supporting evidence - dolphins and spiny anteaters

Answer 17

both of these mammals have an abnormally large cortex, presumably because they cannot ‘unlearn’ through REM and must store everything they have ever seen and heard

Question 18

Reorganisational theory

Evaluation

Answer 18

Most mental illnesses could be defined in terms of ‘faulty learning’.
- might paranoid schizophrenia be the result of hallucinatory/bizarre thought connections
- might obsessive disorders be a result of obsessive thoughts persisting in the mind
- could depression result from the brain becoming ‘jammed up’ with negative or disorded memories

Question 19

Reorganisational theory

Strengths

Answer 19

• gives a good explanation for why we sometimes can’t remember our dreams
• gives a clear theory about why REM sleep might be important
• proposed that a reverse learning mechanism in REM sleep removes certain undesirable models of interaction in neural networks within the cerebral cortex

Question 20

Reorganisational theory

Weaknesses

Answer 20

• based largely on computer models rather than human participants and lacks research support, therefore lacks validity
• there is more evidence to support REM sleep strengthening memories than weakening the memory for anything
• does not explain why most of our dreams make sense and follow a narrative as it doesn’t fit well with the idea that random memories are being activated and destroyed
• how does the brain decide which memories to keep and which to unlearn?

Question 21

Czeisler et al’s (1990) study into shift work

Aim

Answer 21

to show the link between dark/light cycles and circadian rhythms.

aimed to show that properly timed exposure to bright light can re-set the pacemaker by up-to 12 hours in 2-3 days

Question 22

Czeisler et al’s (1990) study into shift work

Method - during the 1st week

Answer 22

For the first week of each participant’s 2 week study period, baseline temperature, physical activity and heart rate were obtained and then the participant completed a week of night shift work. The men lived at home during the study and reported to the laboratory at night.

Question 23

Czeisler et al’s (1990) study into shift work

Method - Dor 4 nights …

Answer 23

For 4 nights, the men in the experimental group (Group 1) were exposed to bright lights from 00.15am - 07.45am. Whereas those in the control group (Group 2) experienced light which was normal room light. All participants completed cognitve tasks each hour in which they had to correctly add up as many pairs of 2 digit numbers as possible in 4 minutes.

Question 24

Czeisler et al’s (1990) study into shift work

Method - during the night …

Answer 24

Those in the experimental group (Group 1) were instructed to remain in the dark in their bedrooms from 09.00am to 17.00pm each day. Those in the control group (Group 2) were told not to remain in the dark at any specific time. Most closed their existing curtains while they slept at a time of their own choosing. The circadian rhythms were monitored and the lowest body temperature time was noted. Blood samples were taken to measure blood plasma cortisol concentrations. The volume of urine was measured at 3 hour intervals.

Question 25

Czeisler et al’s (1990) tudy into shift work

Results - temperature

Answer 25

Temperature had been on average lowest at 04:59am in the baseline week. In the experiemental group (Group 1) their lowest body temperature was occuring 9.6 hours after the baseline of the previous week.

Question 26

Czeislar et al’s (1990) study into shift work

Results - circadian rhythms

Answer 26

There was a failure of the control group (Group 2) to change their circadian rhythm to suit night work. The men in the experimental group (Group 1) exposed to bright light and darkness from 09.00am - 17.00pm changed their circadian rhtyhm for all measures.

Question 27

Czeislar et al’s (1990) study into shift work

Conclusion

Answer 27

Cziesler et al concluded that ‘maladaption of the human circadian rhythm to shift work can easily be treated with scheduled exposure to bright light during the night’.

Question 28

Czeislar et al’s (1990) study into shift work

Strengths

Answer 28

• good control of conditions in a lab experiment when most prior research has been a field experiment
• multiple physiological and behavioural assessments were used to provide robust findings that were in agreement
• the time difference between the mean low point of body temperature in the control group versus the experimental group was statisfically significant and unlikely to have occurred by chance

Question 29

Czeislar et al’s (1990) study into shift work

Weaknesses

Answer 29

• the study used a very small sample that contained only men so it was difficult to generalise to the whole working population
• lacks ecological validity as it is taking people out of their normal environment

Question 30

Czeislar et al’s (1990) study into shift work

Applications

Answer 30

• possible implications for industrial productivity and safety of people on night shift
• highlighted possible health consequences of sleep deprivation and disruption of the circadian rhythm such as cardiovascular, digestive or sleep disorders
• caused many companies to brightly light their workplaces at all times to ensure shift work is not harmful.