The acting brain Flashcards
There are potentially an infinite number of motor solutions for acting on an object
Degrees of freedom problem
Stored routines that specify certain motor parameters of an action (ex: the relative timing of strokes)
Motor programs
A cluster of perceptual processes that relate to the skin and body, and include touch, pain, thermal sensation and limb position
Somatosensation
Knowledge of the position of the limbs in space
Proprioception
Linking together perceptual knowledge of objects in space and knowledge of the position of one’s body to enable objects to be acted on
Sensorimotor transformation
The problem of explaining volitional acts without assuming a cognitive process that is itself volitional (‘a man within a man’)
Homunculus problem
Responsible for execution of voluntary movements of the body
Primary motor cortex
Damage to one side of the primary motor cortex results in a failure to voluntarily move the other side of the body
Hemiplegia
The sum of the preferred tunings of neurons multiplied by their firing rates
Population vector
The lateral area is important for linking action with visual objects in the environment; the medial area is known as the supplementary motor area and deals with self-generated actions
Premotor cortex
Deals with well-learned actions, particularly action sequences that do not place strong demands on monitoring the environment
Supplementary motor area (SMA)
Repeating an action that has already been performed and is no longer relevant
Perseveration
Impulsively acting on irrelevant objects in the environment
Utilization behavior
An organized set of stored information (ex: of familiar action routines)
Schema
The mechanism that selects one particular schema to be enacted from a host of competing schemas
Contention scheduling
The subjective feeling that voluntary actions are owned and controlled by the actor
Sense of agency
A representation of the motor command (a so-called efference copy is used to predict the sensory consequences of an action
Forward model
The phenomenon that voluntary actions and their sensory consequences appear closer together in time than they really are
Intentional binding
The ability to reproduce the behavior of another through observation
Imitation
A neuron that responds to goal-directed actions performed by oneself or by others
Mirror neuron
The inability to use vision to accurately guide action, without basic deficits in visual discrimination or voluntary movement per se
Optic ataxia
A part of the occipitoparietal cortex that responds, in particular, to reaching movements
Parietal reach region (PRR)
A part of the intraparietal sulcus that responds, in particular, to manipulable shapes or 3D objects (from vision or touch)
Anterior intraparietal area (AIP)
A part of the intraparietal sulcus that responds to objects close to the body and in body-centered (as opposed to gaze-centered) coordinates
Ventral intraparietal area (VIP)
The feeling that an amputated limb is still present
Phantom limb
An object that affords certain actions for specific goals
Tool
Structural properties of objects imply certain usages
Affordances
An inability to produce appropriate gestures given an object, word or command
Ideomotor apraxia
A disease associated with the basal ganglia and characterized by a lack of self-initiated movement
Parkinson’s disease
A reduction in movement
Hypokinetic
An increase in movement
Hyperkinetic
A genetic disorder affecting the basal ganglia and associated with excessive movement
Huntington’s disease
A psychiatric disorder with an onset in childhood characterized by the presence of motor and/or vocal tics
Tourette’s syndrome
