perception and attention

Question 1

define sensation

Answer 1

The stimulus detection system by which our sense organs respond to and translate environmental stimuli into nerve impulses that are sent to the brain  ‘Is there anything out there?’

Question 2

define perception

Answer 2

The active process of organising the stimulus output and giving it meaning  ‘What is it, where is it, what is it doing?’

Question 3

perception is an active process

• top down
• bottom up

Answer 3

Top-down
• Processing in light of existing knowledge • motives, expectations, experiences, culture • E.g. ‘backmasking’

Bottom-up
• Individual elements are combined to make a unified perception

Question 4

factors affecting perception (top down)

Answer 4

Attention (more on this later) 

Past experiences  Poor children and adults overestimate the size of coins compared to affluent people (Ashley et al., 1951) 

Current drive state (e.g. arousal state)  Hunger: when hungry, more likely to notice food-related stimuli (Seibt et al., 2007) 
Emotions  Anxiety increases threat perception (e.g. in PTSD) 
Individual values & expectations  Telling people a stimulus might be painful makes them more likely to report pain in response to it (Colloca et al, 2008) 

Environment (see next slide) 

Cultural background

Question 5

Perceptual Organisation – Gestalt Laws

Answer 5

Early 20th century psychologists set out to discover how we organise the parts of our perceptual field into a whole.
 Championed ‘top-down’ processing (the sum of the parts is more than the whole)
 Figure-ground relations: our tendency to organise stimuli into central or foreground and a background.  Focus of attention becomes the figure, all else is background

Question 6

gestalt laws

-continuity

Answer 6

Continuity: When the eye is compelled to move through one object and continue to another object

Question 7

gestalt laws:

similarity

Answer 7

Similarity: Similar things are perceived as being grouped together

Question 8

gestalt laws

proximity

Answer 8

Proximity: Object near each other are grouped together

Question 9

gestalt laws

-closure

Answer 9

Closure: Things are grouped together if they seem to complete some entity.

Question 10

visual agnosia

Answer 10

Basic vision spared  Primary visual cortex can be mostly intact  Patient not blind  Knowledgeable about information from other senses (e.g. if they touch an object then naming is typically simple)
 Associated with bilateral lesions to the occipital, occiptotemporal, or occipitoparietal lobes.

Question 11

apperceptive agnosia?

Answer 11

Apperceptive Agnosia: A failure to integrate the perceptual elements of the stimulus.  Individual elements perceived normally  May be able to indicate discrete awareness of parts of a printed word but cannot organised into a whole  Damage to lower level occipital regions

Question 12

associative agnosia?

Answer 12

Associative Agnosia: A failure of retrieval of semantic information  Shape, colour, texture can all be perceived normally  Typically sensory specific e.g. if object touched, then recognised  Damage to higher order occipital regions

Question 13

object recognition

Answer 13

diagram

Question 14

attention informing perception

Answer 14

Attention is the process of focusing conscious awareness, providing heightened sensitivity to a limited range of experience requiring more intensive processing.

Question 15

2 process of attention informing perception

Answer 15

2 processes:  Focus on a certain aspect  Filter out other information

Question 16

-

Answer 16

Focused attention  The ‘spotlight’

 Divided attention  Paying attention to more than one thing at once

Question 17

stimulus factors affecting attention

Answer 17

intensity 
novelty 
movement 
contrast 
repetition

Question 18

personal factors affecting attention

Answer 18

motives 
interests 
threats
mood 
arousal

Question 19

define attention

Answer 19

Intertwined with other cognitive processes (e.g. memory and perception) • Sensory buffers register information for a few seconds which can be used to select which information to focus on. • Limited capacity for short term memory • But, there is evidence that we can unconsciously perceive information not attended to.

Question 20

cocktail party effect

Answer 20

We can focus our attention on one person’s voice in spite of all the other conversations
• But, what happens when someone says your name in another conversation nearby?

Question 21

attention and clinical skills

Answer 21

• Development of mental resources • Learning requires explicit instruction through teaching from an ‘expert’, demonstration, and self-observation. • An effective motor programme has been developed to carry out the broad skill but lacks ability to perform finer subtasks with fluency • The skill is largely automatic • Rely on implicit knowledge and motor co-ordination, rather than instruction

Question 22

perception of bodily symptoms

Answer 22

Focus of attention contributes to the perception of our bodily symptoms  Perception of symptoms whilst jogging on a treadmill (Pennebaker & Lightner, 1980)

Question 23

Acute Pain: Expectation of perceived bodily symptoms

Answer 23

Stimulus: vibrating piece of sandpaper  Students were told they would be: 
Painful 
Pleasant 
Not told anything

Question 24

chronic pain

Answer 24

Pain is usually a sign of body damage • Chronic pain is when pain has been present for greater than 3 months
-diagram

Question 25

gate theory of pain

Answer 25

Gate Theory of Pain (Melzak, 1999)
• Pain signals compete to get through ‘gate’ • ‘Gate’ can be opened or closed by psychological and physical factors. • Explains pain relief by ‘rubbing it better’

Question 26

fear avoidance model of chronic pain

Answer 26

• Strong relationships between areas • Pain breeds avoidance which perpetuates stress, low mood, anxiety etc

-model