Introduction to cognitive neuropsychology

Question 1

What are the two causes of Amnesia

Answer 1

Organic: Damage from injury or damage from disease

Psychogenic: purely psychological

Question 2

What are the two forms of Amnesia

Answer 2

Retrograde: Can’t recall memories formed in the time leading up to the injury but can sometimes remember childhood memories

Anterograde: Not able to form new memories after the onset of amnesia

Question 3

What are the main features of Amnesic Syndrome

(relatively pure amnesia meaning there are no other problems i.e. no language problems)

Answer 3

• Retrograde amnesia
• Anterograde amnesia
• In tact short term memory
• Skills such as driving are not affected
• Preserved general intelligence (IQ)
• Some residual learning capacity for motor skills usually

Question 4

What are some causes of Organic Amnesia

(organic amnesia means biological so damage to the brain)

Answer 4

• Amygdala - episodic memories
• Basal Ganglia - Learning of motor skills
• Cerebellum - Storage of motor skills
• Frontal Lobes - Working memory
• Occipital lobes - Visual perception and memory
• Hippocampus - long term memories

Question 5

Effects of damage to the hippocampus

Answer 5

• Patient HM had hippocampus and amygdala removed
• His epilepsy improved and his personality did not change
• Unable to form new episodic memories
• Severe anterograde amnesia
• He could learn new procedural memories

Question 6

Korsakoff’s Syndrome

Answer 6

• Happens because of thiamine deficiency
• A thiamine deficiency occurs as a result of alcoholism
• The thiamine deficiency causes damage to diencephalon
• Patients seem as though they are drunk and have no coordination, they are also confused
• Retrograde amnesia going back years or even decades
• Short term memory is normal

Question 7

Viral Encephalitis

Answer 7

• Caused by herpes virus
• Causes damage to the temporal lobe
• Clive Wearing suffered with Severe amnesic disorder
• Problems with facial recognition also dyslexia

Question 8

Non Pure Amnesia as a result of Dementia

Answer 8

• Most common type of dementia is Alzheimer’s disease
• Dementia is very common
• Progressive neural disorder
• Growth of neural plaques
• Alois Alzheimer, described his patient as having memory loss, hallucinations ‘unusual disease of the cerebral cortex’

Question 9

Contextual Cues in Amnesia
Oliver Sacks, Music and memory in Alzheimers

Answer 9

• People Alzheimers are able to remember songs
• Listening to music also brings back memories from that stage in their life

Question 10

Medication and Amnesia

Answer 10

• Viagra, had been shown to cause amnesia

Question 11

What is Transient Global amnesia

Answer 11

• Sudden onset of anterograde and retrograde amnesia
• No loss of personal identity, still recognise family
• Resolves within 12 hours
• More common in men over 50
• May be as a result of emotional distress or extreme exercise

Question 12

Amnesia and dissociations between different types of memory

Answer 12

• Amnesia provides evidence that there should be a separation between long and short term memory
• Amnesia also helps with the distinction between episodic memory and semantic memory
• Amnesics show recency effect because they can still use short term memory

Question 13

Theories of Anterograde Amnesia

Answer 13

Why can’t amnesics store or code new memories:
- Faulty encoding
- Accelerated forgetting
- Faulty retrieval
- Faulty encoding/ storage of contextual information

Question 14

Problems with initial encoding
Cermak (1979)

Answer 14

• Lack of deep encoding
• ## Not very good at learning word pairs such as ‘hungry’ and ‘thin’ - levels of processing theory

Question 15

Accelerated Forgetting
Huppert & Piercy, (1979)

Answer 15

• People who have lesions on their hippocampus forget things a lot quicker than controls even after they have learnt the material properly

Question 16

Retrieval Deficit
(Aggleton & Shaw, 1996)

Answer 16

• Recognition is sometimes unimpaired in amnesics
• Recall is always impaired

Question 17

A Test of contextual deficit theory
Huppert and Piercy (1976):

Answer 17

• Amnesic (korsakoff) patients and control patients
• Presented set of pictures on day on and day two, some were present on both days
• Recognition task, participants had to say if they had seen image at all (regardless of day) and also if they had seen certain pics only on day two.
• Results showed no diff between groups on if they had seen picks
• However, Amnesic patients were poorer at recognising if the picture had been seen on day two but they also though that many pictures they had seen on day one were seen on day two.

Question 18

Contextual Deficit Theory Problems

Answer 18

• Semantic memories can be impaired and these aren’t contextual
• Context definition is vague
• Context-processing deficits vary substantially across patient groups (e.g., Parkin & Hunkin, 1997; Squire, 1982).

Question 19

Temporal gradient in retrograde amnesia

Answer 19

• Butters and Cermak (1986), Amnesic patient had written a autobiography so could use this to ask questions.
• Couldn’t remember anything 20 years prior although could remember from childhood.
• This is because of a consolidation process

Question 20

Consolidation Theory of retrograde amnesia
(Dudai, 2004; Squire, 1992)

Answer 20

• Initially episodic memories are stored in the hippocampus
• To access these memories the hippocampus has to be reactivated
• Overtime, the cortex can retrieve these memories without the hippocampus
• Thus, older memories aren’t affected by amnesia

Question 21

Two types of Psychogenic Amnesia

Answer 21

• Fague states
• Dissociative Amnesia

Question 22

Fugue states

Answer 22

• Patients usually found wondering a long way from home
• Triggers are stress and depression
• Can last from a few hours to a few days
• When recovered, memories from the fugue state are lost
• Very rare

Question 23

Dissociative type

Answer 23

• Loss of memory for specific events as a result of trauma
• Very rare
• 25-45% of murder suspects claim amnesia for the crime