9. Attention + perception

Question 1

What is perception?

Answer 1

The active process of organising the stimulus output and giving it meaning (the step after ‘sensation’)

Question 2

What are ‘top-down’ factors affecting perception?

Answer 2

Processing in light of existing knowledge:
• Attention
• Pat experiences
• Current drive state
• Emotions
• Individual values + expectations
• Environment (upbringing and culture)
• Cultural background

Joins with the ‘bottom-up’ factors to form the best interpretation of the stimulus

Question 3

What are the ‘bottom-up’ factors affecting perception?

Answer 3

• Individual elements are combined to make a unified perception
• Refers to the idea that that the nerve impulses we receive from senses activate higher cortical areas in order for us to perceive them
• e.g. acoustic wave => vibration => activation of auditory cortex

Joins with ‘top-down’ factors to form the best interpretation of the stimulus

Question 4

What are figure-ground relations?

Answer 4

Our tendency to organise stimuli into central/foreground and a background

Question 5

What are the Gestalt laws of grouping?

Answer 5

• Set of principles that account for figure-ground relations: similarity, proximity, good form, closure, common fate, continuation
• Humans naturally perceive objects as organised patterns
• The sum of the parts is more

Question 6

What is ‘continuity’ in the Gestalt laws?

Answer 6

• When the eye is compelled to move through one object and continue to another object
• Plays on the idea that we look for continuity of movement and flow, when we perceive things

Question 7

What is ‘similarity’ and ‘proximity’ in the Gestalt laws?

Answer 7

• Similarity - similar things are perceived as being grouped together
• Proximity - objects near each other are grouped together

Question 8

What is ‘closure’ in the Gestalt laws?

Answer 8

• Things are grouped together if they seem to complete some entity
• If a picture has several parts of it missing, our brains will very quickly close this gap up

Question 9

What is visual agnosia?

Answer 9

• Only visual recognition is impaired
• Pure visual pathways of the occipital lobes are damaged
• Primary visual cortex can mostly be intact and basic vision is spared
• If a patient holds an object (tactile sensation), they can often recognise it

Question 10

What is apperceptive agnosia?

Answer 10

• Very basic elements of visual perception are damaged
• Failure to integrate the perceptual elements of the stimulus into a whole
• Individual elements perceived normally
• Can’t put all fo the pieces of an object (colour, size, shape etc.) to form the object so can’t say what it is

Question 11

What is associative agnosia?

Answer 11

• Basic components are ok
• Damage is further up the pathway - higher order occipital regions
• They can put all of the pieces together
• However, they cannot recall facts about it e.g names, use etc.

Question 12

Are the earlier or later stages of visual processing involved in figure-ground segmentation (separating stimulus from the background)?

Answer 12

Early stages

Question 13

What is attention?

Answer 13

The process of focusing consciousness awareness, providing heightened sensitivity to a limited range of experience requiring more intensive processing.

Question 14

What are the 2 types of attention?

Answer 14

• Focused attention - focusing on something specific and ignoring other stimuli
• Divided attention - paying attention to more than one thing at once

Question 15

What stimulus factors affect attention?

Answer 15

• Intensity
• Novelty
• Movement
• Contrast
• Repetition

Question 16

What personal factors affect attention?

Answer 16

• Motives
• Interests
• Threats
• Mood
• Arousal

Question 17

Why is attention important?

Answer 17

• Heavily intertwined with other cognitive processes
• Can’t learn properly if we don’t attend to the information in front of us
• Gateway to cognition
• Affects our short-term memory - which is then encoded and stored onto our long-term memory

(evidence that we can perceive information not attended to)

Question 18

What is the digit span test?

Answer 18

• Read a number of digits in a row
• Ask the patient to repeat it back
• Tests attention

Question 19

What is the Cocktail Party effect?

Answer 19

• We can focus our attention on one person’s voice in spite of all the other conversations
• But, when someone says your name in another conversation nearby, you will pay attention to it
• We struggle to recall any information from any conversation we do not focus on

Question 20

What are the 3 stages of attention?

Answer 20

• Cognitive - development of mental resources, explicit instruction through teaching, demonstration and self-observation
• Associative - motor programme developed to carry out the broad skill, lack of ability to perform finer subtasks
• Autonomous - largely automatic

Question 21

How is conscious control affected, the more automatic a task is?

Answer 21

Less conscious control e.g. driving

Question 22

Can stress and anxiety affect automatic behaviour?

Answer 22

Yes - error due to automatic behaviour has been a direct cause of over half of patient deaths

Question 23

What is medical student syndrome?

Answer 23

• Students taught a lot of medicine
• They begin to develop anxious thoughts and think they have problems
• Start to mention symptoms in their body
• i.e. normal bodily sensations like headaches, coupled with medical teaching => catastrophic perception => anxiety

conflicting studies on MSS

Question 24

Can auditory perception change physical perception?

Answer 24

Yes - study showed that people walking on a treadmill listening to street sounds perceived physical symptoms much less

Question 25

Can upcoming acute pain be altered by changing someones expectation?

Answer 25

Yes - students told that touching a vibrating piece of sandpaper would be pleasant or painful, felt it more like it was described to them

Question 26

What is acute and chronic pain?

Answer 26

• Acute - pain experienced for a short amount of time, directly related to tissue damage, generally starts to heal
• Chronic - pain experienced for a longer period of time (>3 months), original damaged has probably healed, with lots of psychological factors influencing the way it is experienced and perceived

Question 27

What is the Gate Theory of Pain?

Answer 27

• Pain signals compete to get through a ‘gate’ in the dorsal horn of the body
• Can be opened or closed by psychological and physical factors e.g. rubbing it better
• Our emotions, stress levels, previous experience and beliefs can effect perception of pain
• Higher levels of stress and depression can cause sensitisation of neurones and a loss of control of this gate

Question 28

Can pain just be purely brain-related?

Answer 28

Yes - chronic pain
• Many areas of the brain perceive pain
• Includes areas involved in emotion e.g. amygdala
• Also some involvement from pre-frontal cortex (personality and thinking)
• Can be made worse as chronic pain makes people avoid things, which increases the likeliness to feel low and anxious - cycle

Question 29

How can we physically see the areas of the brain involved in chronic pain?

Answer 29

These areas light up in fMRI