Section 4 Notes Flashcards
Define: anticipation
Broadly defined as being prepared for what and when a signal cueing one to move occurs
Explain the following from the slippery surface research example given:
- what was manipulated
- what did the manipulation cause
- how did the results support the take-home message?
- manipulated: prior knowledge of if the floor was slippery or not (anticipation)
- what did the manipulation cause: decreased foot angle, decreased horizontal foot force, slower foot weight shift time)
- take home message: anticipation of an upcoming perturbation affects the response
Differentiate between effector anticipation and temporal anticipation
Effector anticipation: predicting the duration of internal processes for a planned movement so that it can be made to coincide with some anticipated external event (batter having to decide when to initiate swing with arrival of ball)
Temporal anticipation: The ability to anticipate when a stimulus will occur
Define foreperiod then explain how foreperiod affects temporal anticipation
foreperiod: interval between warning cue and stimulus onset
- regularity of foreperiod: a constant foreperiod results in a shorter reaction time because one can predict the duration and thus knows when the stimulus will appear
- duration of foreperiod: too short leads to increased reaction time and too long. too long leads to increased reaction time when catch trials are intermixed (trials where stimulus is withheld). too long with no catch trials leads to shorter reaction time
Give 2 definitions for attention
- the information processing capacity of an individual (this definition says attention has a fixed capacity; you can only attend to so much)
- the preparedness for and selection of certain aspects of our physical environment… (example: a cat stalking its prey is so focused on the action that it ignores all other attention seeking stimuli
Explain the following from the pre-cue paradigm research example given:
- what was manipulated
- what did the manipulation cause
- how did the results support the take-home message?
- manipulated: attention (pre-cues were neutral, incorrect, or correct)
- influenced: reaction time; (valid pre-cues shortened reaction time and invalid increased reaction times; neutral cues were considered controls)
- how the results supported message: attention (2nd definition) influences reaction time
Describe the following in a dual task paradigm
- logic/ assumptions
- primary task
- types of secondary task
- logic: information processing capacity (attention) is limited; if 2 tasks are performed simultaneously and require more than the total capacity available to the individual, then performance diminishes
- primary task: usually motor behaviour (walking, reaching, standing)
- types of secondary task: continuous, discrete (at various times participant must respond to stimulus throughout primary task)
Capacity interference is a measure of what? Define capacity interference
- measure of attention
- Measured as a decline in performance due to limited central capacity (i.e., attention) if structural interference can be ruled out
Explain how structural interference is different from capacity interference
- structural interference: decreased performance caused by physical structures and not attention limits
- example: hand having to make movements in both tasks
Explain how vocalized counting is a structural interference to postural sway
Counting causes changes in breathing, which impacts postural
sway. Can’t argue performance change is due to attention capacity issues since the act of talking influences sway.
Explain the following from the dual tasking during standing research example given:
- what was manipulated
- what did the manipulation cause
- how did the results support the take-home message?
- manipulated: attention; standing perturbation while performing a secondary task (tracking)
- manipulation caused: tracking paused
- take home message: Notice in panel C a deviation of tracking occurs 100-300 ms after perturbation onset; this supports the notion that later phase of the recovery response requires cognitive (cortical) processing (and that the participant priorities balance over tracking)
What is a useful clinical test or observations of fall risk among older adults?
- reduced gait speed in older adults when walking and talking
- stop walking while talking may predict that distractions could put attention over capacity leading to collision/tripping/falling
- increased gait variability when walking and talking (predicts future and multiple falls)
Define: executive function
let people plan, organize, and complete tasks. Includes attention, working memory, cognitive flexibility (or flexible thinking), and inhibitory control (or self-control; being able to ignore distractors)
What are some interventions that can improve cognitive function, multitasking ability, and reduced falls in older adults.
- attention demanding video games
- exercising to improve cognitive skills
- exergaming! training attention with interactive game while exercising
Define: arousal
an internal state of alertness or excitement
Define: anxiety
the emotional and cognitive impact of arousal, such as nervousness or tension
Describe the inverted-U relation and the zone of optimal functioning
- inverted-U relation: optimal performance requires moderate arousal levels; low and high levels of arousal lead to declines in performance
- zone of optimal functioning: Zone defining a range of arousal levels for optimal performance; Depends on individual and task
How does a perceived threat affect walking?
- slower gait speed as a cautious gait strategy; example: walking at the edge of a cliff, walking in the dark, walking across an unstable terrain
- gaze fixation strategies altered: you may focus on a narrow region of space or you might look in all directions
Many researchers believe that there are three stages of information processing that occur before a movement is made in response to a stimulus. This is so-called cognitive processing. What are these 3 stages? Do they occur sequentially or simultaneously
- stimulus indentification
- response selection
- response programming
- modern view is simultaneous (so response selection and programming can happen at the same time)
Describe the stimulus identification stage in information processing.
- stimulus must be identified or recognized as part of a pattern
- then must be transformed into action potentials set into brain for further processing
- Stimulus can be visual, tactile, auditory, a combination, etc.
Describe the response selection stage in information processing.
- The decision of whether to respond and which response to select
- Factors influencing response selection, and hence reaction time include:
• # of choices (or stimulus-response [S-R] alternatives)
• S-R compatibility
Describe Hick’s law, give the equation, and give the exceptions where it does not uphold
- Shows that with more alternatives, there is increased reaction
time, suggesting more central processing (relationship between choice RT and # of S-R alternatives) - equation: Choice RT = m[Log2(N)] + b
- Where N is the # of S-R alternatives, m is the slope, and b is the intercept
- exceptions: familiarity with the task, having a predictable task
Define a bit in Hick’s law and describe the relationship it has with S-R alternatives
- 1 bit is defined as the amount of information needed to reduce the original uncertainty by half
- 0 bit = 1 S-R alternative
• 1 bit = 2 S-R alternatives
• 2 bits = 4 S-R alternatives
• 3 bits = 8 S-R alternatives
What information does the intercept and slope of Hick’s law provides?
- intercept: measure of the overall ‘speed’ of the sensory and motor system
- Slope: measure of the decision making ‘speed’ during the
response-selection stage (ms/bit); i.e., how much additional time does each additional choice add to RT?
