Task 1 Flashcards
Binkofsky methods
- measure: RT + errors
- conditions: conflict = different actions [calculator] / non-conflict = same actions [cup]
Binkofski relevant concepts
- object affordances = potential actions individuals perceive when interacting with the environment
- use = highly skilled interactions
- grasp = basic interactions
Binkofski results
- use (function based actions) = slower for conflict objects
- grasp (structure based actions) = slower ONLY for conflict objects when preceded by “use”-task
- use-then-grasp = slower –> inference with lasting representations in the ventral system
Binkofski discussion
- conflict objects = grasping has a slower initiation time –> interference by preceding use task
- representations remain longer in the ventral (use) system, than in the dorsal (grasp) system
what are structure-based activations?
- grasping
- fast
- degrade quickly
what are function-based activations
- using
- slower
- last longer = produce interference effects in dorsal grasp system
Binkofski brain
- use system
= function-based activations
= ventro-dorso system - grasp system
= structure-based activations
= dorso-dorsal system
Sumner methods
- patient CB (SMA + SEF damage)
- patient JR (SEF damage)
- prime + mask + target
- response via L/R clicks to indicate where target appeared
- measure: eye + manual response
Sumner relevant concepts
- negative compatibility effect (NCE) = responses are slower for compatible than incompatible primes
- positive compatibility effect (PCE) / facilitatory priming = responses are faster for compatible than incompatible primes
Sumner results
- patient CB (SMA & SEF damage): PCE occurred in both responses -> failed inhibition
- Patient JR (SEF damage): PCE occurred only in eye responses, NCE in manual responses
- Controls: NCE in both
Sumner discussion
- medial frontal cortex (SMA/ SEF) show effector-specific (= eyes/ hands) automatic motor inhibition
Sumner Brain
- SMA:
> responsible for inhibition of manual movements
> action selection (WONG) = automatic inhibition of unwanted responses - SFA: responsible for inhibition of eye movements/ saccades
Passingham methods
- fMRI
- tasks with self-generated + externally triggered action
- self-generated: initiation/ execution of a voluntary action (based on a specific cue or instruction) -> in the dark
- externally triggered: participants respond to externally presented stimuli/ cues to perform an action
Passingham results
- incrased activation of (Pre) SMA during
> self-generated movement
> cues to perform an action
Passingham brain
- MFC is involved in the generation of self-initiated actions
- MFC is engaged in evaluating and monitoring outcome of self-initiated actions
- preSMA is active during self-generated movement + evaluation
What does the WONG scheme express?
- provides an organisation of the brain for voluntary action
- differentiates between WHAT (= identifying the motor goal) + HOW (=executing an action to achieve the motor goal)
What are the components of WONG´s schema?
- WHAT (= selection of motor goals)
> Task
> Observation of Environment
> Object selection - HOW
> Abstract Kinematics
> Action selection
> Movement specification
What is the difference between Wong and Passingham (Wong scheme)
Action selection
- WONG: how process (=selection of motor goal)
- PASSINGHAM: what process (= selection of appropriate responses)
What are the exogenous paths of action?
- dorsal stream (V1/V2 -> MT/ V5)
> HOW - ventral stream (V1/V2 -> V4)
> WHAT
Dorsal stream
- How
- mediates navigation and visual control of skilled actions (directed at objects in the real world)
- V1/V2 –> MT/V5
ventral stream
- WHAT
- transforms visual inputs into representations embodying enduring characteristics of objects + their spatial relationship
- V1/V2 –> V4
Dorso-dorsal pathway
- most direct visual pathway for actions associated with online actions
- ACTION: reaching towards targets with various locations in space
- V3a -> V6 -> V6a/ medial intraparietal area (MiP) -> dPMA
- involved in GRASP- SYSTEM
Ventr-dorsal stream
- underlies processing of sensorimotor information (based on longer-term object use representations)
- medial temporal lobe -> inferior parietal lobe -> dPMA
- involved in Use system
ideomotor apaxia
- left hemisphere, parietal cortex
- ventro-dorsal stream
- Impairment in the execution of learned motor sequences
- difficulty following complex motor commands
- patient can still perform those actions automatically/ spontaneously
optic ataxia
- damage to parietal cortex
- dorso-dorsal stream
- difficulty in accurately reaching for visual targets in space despite having normal visual perception
Alien Hand syndrome
- damage to corpus callosum (connecting hemispheres)
- involuntary of one hand, often accompanied by feeling that affected hand is moving out of patient´s control