Attention and Perception

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

stimulus -> sensory receptors -> neuronal impulses -> brain

Question 2

define perception

Answer 2

the active process of organising the stimulus output and giving it meaning

Question 3

what is bottom-up processing

Answer 3

individual elements are combined to make a unified perception

Question 4

what is top-down processing

Answer 4

processing in light of existing knowledge (motives, expectations, experiences, culture)

Question 5

list factors that affect top-down perception

Answer 5

attention being split
past experiences 
current drive state (eg arousal, hunger)
emotions
individual values and expectations 
environment 
cultural background

Question 6

list stimulus factors that affect attention

Answer 6

intensity 
novelty
movement
contrast
repetition

Question 7

list factors which can lead to medical errors

Answer 7

increased autonomous action comes automatically after repetition and skill increase but means that errors are more likely to occur

stress, anxiety and tiredness can negatively impact performance

Question 8

list factors that influence pain perception

Answer 8

expectation changes the response to the same stimuli - if the patient is told it will hurt they will experience hurt

also related to conditioning - avoiding pain decreases pain therefore avoidance increases however this avoidance behaviour can lead to stress and anxiety

Question 9

list Gestalt Laws (6 of them)

rules of the organisation of perceptual scenes

Answer 9

Figure-ground relations: our tendency is to organise stimuli into central or foreground and background

continuity: when the eye is compelled to move through one object and continue to another

common fate: elements that move together (and therefore have a similar fate) are grouped together

similarity: similar things are perceived as being grouped together
proximity: objects near each other are grouped together
closure: things are grouped together if they seem to complete some entity (wwf logo)

Question 10

what is visual agnosia

Answer 10

patient can see but cannot recognise or interpret what they are seeing

basic vision is spared and the patient is not blind. the primary visual cortex is mostly intact and the patient is knowledgeable about information from other senses

it is associated with bilateral lesions to the occipital, occiptotemporal or occipitoparietal lobes

Question 11

what is apperceptive agnosia

Answer 11

a failure to integrate the perceptual elements of the stimulus

the individual elements are perceived normally but they are not put together into a whole

Question 12

what is associative agnosia

Answer 12

a failure of retrieval of semantic information

perception occurs but recognition does not

shape, colour, texture can be perceived normally
damage to higher order occipital regions

Question 13

what is the Hierarchical model of visual perception

Answer 13

visual perceptual analysis

viewer centred representation

visual object recognition

semantic system

name retrieval

(down arrows between each)

apperceptive agnosia affects visual perceptual analysis and viewer centred representation

associative agnosia affects visual object recognition system and semantic system

Question 14

define attention

Answer 14

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

2 processes involved:
focus on certain aspect
filter out other information

Question 15

what are the components of attention

Answer 15

focused attention (the spotlight)

divided attention (multitasking on several things at once)

Question 16

list personal factors that affect attention

Answer 16

motives 
interests
threats
mood
arousal

Question 17

define the cognitive stage of attention and learning

Answer 17

development of mental resources

learning requires explicit instruction through teaching from an expert, demonstration and self-observation

Question 18

define the associative stage of attention and learning

Answer 18

an effective motor programme has been developed to cary out the broad skill but lacks ability to perform finer subtests with fluency

Question 19

define the autonomous stage of attention and learning

Answer 19

the skill is largely automatic

relies on implicit knowledge and motor coordination rather than instruction