Week 1-2 Variables & Visual Attention Flashcards
How to avoid ceiling/floor effects in cognitive studies?
Ceiling effects imply that the task is not difficult enough; while floor effects imply the task is too difficult.
It could imply that reaction speed or accuracy is being overly prioritised, resulting in overly fast or slow results. To reduce these effects, reaction time should be always compared with accuracy, which need to be optimised to an appropriate level of difficulty.
What is Signal detection theory?
Sensitivity vs response bias
Used in uncertain contexts
is a framework that discriminates a participant’s sensitivity of a target from their response bias, which refers to their tendency to respond to the target in a particular way (liberal vs. conservative)
What is signal detection theory used for?
Used in diagnosis, visual search tasks, when something may have been present
Used in force choice paradigms about detecting a target or what that target was
What are the 4 different responses in signal detection theory? (H-CR-M-FA)
- Hit = present, says present
- Correct rejection = not present, says not present
- Miss = present, says not present
- False alarm = not present, says present
What is the difference between top-down and down-top attention?
Exogenous (down top) = attention is captured by salient bright, loud or intense stimulus that is unpredictable and is not goal-relevant
Endogenous (top down) attention is captured by longer, informative and predictable or goal-relevant cues by the individual, ie. purposely looking for something
What is the the early-attention theory? (Cherry, Treisman)
States that things are sensed from the environment, filtered out early before undergoing semantic analysis in the LTM
What is the the late-attention theory? + example
- late selection processing states that irrelevant information still goes through semantic analysis before being filtered out after being deemed irrelevant
Example - hearing name in unfiltered stream
What is Lavie’s perceptual load Theory and how does it combine both early and late attention theories?
The theory states that perceptual load may be seen as a mediating factor between whether information is processed at an early/late stage
- If perceptual load is high, (tons of stuff in the environment), then non-target stimuli is not processed and people are more likely to engage in early stage attention
- Thus late-stage processing can only occur if the cognitive load/environmental stimuli is low
What is exogenous (down top) attention?
- reflexively captured by salient (bright, loud, intense) stimuli in the environment
- very short (100ms), quite unpredictable,
-no goal-relevant utility, captured by salient features of the environment.
What is endogenous (top down) attention?
Attention shifted towards an informative que, longer cues (300ms),
Quite predictable but still arbitrary and goal relevant
How is overt and covert attention measured?
- Overt attention = eye tracking technology
- Covert attention = Posner Cueing Paradigm and RT’s as measurements
How does Posner’s covert paradigm measure covert attention?
- A cue in random location (invalid cues) or exact location as target (valid cues) will show first
- Then you respond to target when shown after the cue
- Slower RT’s for cues further away (invalid cues) compared to cues at exact location (valid cues) convey time taken to shift attention covertly
If response times (RTs) are equivalent on valid and invalid trials in a Posner cueing paradigm, what does this indicate that the cue has done to attention?
If response times (RTs) are equivalent on valid and invalid trials, that infers that the cues did not register in the participants attentional breadth.
As a result, covert attention cannot be accurately measured since the difference in RT times is used as the indicator of covert shift of attention.
Why does inhibition of return occur and when?
Inhibition of return is a negative cueing score, where the invalid cues produce faster responses than the valid cues.
This often occurs after a longer period of time between the cue and the target, and may reflect attention has been disengaged from the cued stimulus.
How does the Dot point paradigm use emotional stimuli to measure the role of emotion in covert attention?
- Exposes participants to emotional salient stimuli as a valid or invalid cue before asking them to respond as quickly as possible to a target,
- It was predicted that those with emotionally-salient cues would be faster at identifying the target where the emotionally salient cue was (congruent trial) and slower at identifying the target where the neutral cue was (incongruent trial)
