Task 1 Flashcards
(12 cards)
Intraparietal sulcus (IPS)
Function
- Represents relevant stimuli
- Part of the basal ganglia attention (occulomotor) loop
FEF (Frontal eye fields)
Function
Representing possible motor goals (saccade targets)
Initially multiple, in the end only the final motor goal
(pre)SMA
Function
- Involved in selecting one action and surpressing the others
- Part of the basal ganglia motor loop
PMd
Function
Movement specification
M1
Function
Movement specification
(lateral) PFC
Function
- Encoding task rules and translating cues in the environment into motor goals
PMv
Function
Involved in action selection
Limb apraxia
A disorder affecting skilled movements of the arms and hands
Ideomotor apraxia: Trouble converting an idea into motor action (e.g., knows what a hammer is, but can’t pantomime hammering).
Ideational apraxia: Impaired sequencing of multi-step actions (e.g., brushing teeth before taking off the cap)
Object apraxia
Problems using objects correctly, especially those with conflicting affordances (e.g., tools that you grasp differently than you use them)
Binkofski & Buxbaum (2013) - Key point
- Found that the distinction between only ventral (“What”) and dorsal (“How”) stream cannot account for the double dissociation between opject and limb apraxia
- Suggest two dorsal routes also (the dorso-dorsal stream and the ventro-dorsal stream)
Binkofski & Buxbaum (2013) - The two dorsal pathways
- Dorso-dorsal stream (“Grasp”): Quick, short processing, damage leads to object apraxia
- Ventro-dorsal stream (“Use”): Longer term processing, more complex
Wong’s scheme
Differentiaties between “What” and “How” connected to each other by motor goals
“What”:
1. Observation of environment (IPS/LIP)
2. Application of task rules (LPFC)
3. Object selection
Motor goals (FEF)
“How”:
1. Action Slection (PMv/(pre)SMA)
(2. Abstract kinematics)
3. Movement specification (PMd/M1)
