skills
- skill memories
- two basic types
- skill = ability that you can improve over time through practice
- skill memories: can’t always be verbalized
- types:
(1) Perceptual-Motor Skills = learned movement patterns guided by sensory inputs (physical)- closed skills = skills, which consist of performing predefined movements, e.g. ballet dancing
- open skills = skills that require participants to respond based on predictions about the changing demands of the environment
(2) Cognitive skills = require to use brain to solve problems or apply strategies (intellectual)
Expertise and Talent
- people with talent: seem to master skill with little effort
- experts: people who perform a skill better than most
- influence of genes:
the more practice –> the more influence of genes- (first environment, then genes)
Practice
- basic idea: the more times you perform a skill, the faster of better you’ll be able to perform in the future
- knowledge of results ( = feedback about performance) is critical
Practice
- Acquiring skills
- fast learning: looking for which brain area to use
- slow learning: structural changes
- power law of learning = “law of diminishing returns”
- feedback is critical; kind of feedback can determine how practice affects performance
- massed practice (=concentrated, continuous practice):: better in short term
- spaced practice (=spread out over several sessions): better in long term
- constant practice (=practice with limited set of materials and skills): repeatedly practicing same skill
- variable practice (=practice with more varied set): practicing skill in wider variety of conditions; better performance in later tests
Practice
- Implicit Learning
= individual can learn to perform a certain skill without ever being aware that learning has occurred; no awareness of learning
(1) perform some task, incidentally learn an underlying skill that facilitates performance
(2) amnesia: make effort to learn skill during each session, but always think they are trying it for the first time
Practice
- Retention and Forgetting
- memorability of a skill depends on:
(1) complexity of skill
(2) how well skill memory was encoded in first place
(3) how often it has been recalled
(4) conditions of which recall is attempted - skill decay = loss of a skill through non-use
- forgetting curves similar to learning curves
- new memories can interfere with recollection of old memories
Transfer of Training
- transfer specificity = restricted applicability of some learned skills to specific situations (e.g. opening a door)
- Thorndike:
- identical elements theory = predicts that tennis player who trained on hard courts might suffer a bit if game were moved to clay courts, and would do progressively worse as the game was changed from tennis to badminton or table tennis
Models of Skill Memory
- motor programs = sequence of movements that an organisms can perform automatically
- either inborn or learned
Models of Skill Memory
- Stages of Acquisition - Paul Fitts
(1) Cognitive stage / fast learning
- performance based on verbalizing rules
- active thinking required to encode the skill
(2) Associative stage / slow learning
- actions become stereotyped
(3) Autonomous stage / asymptotic learning
- movements seem automatic
- skill or subcomponents have become motor programs
- may be impossible to verbalize
Brain Substrates
- Basal Ganglia and Skill Learning
- Basal Ganglia:
- input: from large numbers of cortical neurons
- output: mainly to thalamus and brainstem
- role in initiating and maintaining movement
- disruption impairs skill learning
—> BG important in perceptual-motor learning that involves generating motor responses based on environmental cues
Brain Substrates
- Basal Ganglia and Skill Learning
- Learning Deficits after Lesions –> Standard Radial Maze Task
—> rats search arm in a maze for food, without repeating visits to the arms they have already searched
- hippocampal damage: major problems —> because of spatial map
- basal ganglia damage: no problems
—> other version: food in arms that are illuminated
- hippocampal damage: learn version, only need to associate light with food
- basal ganglia damage: difficulty learning
Brain Substrates
- Basal Ganglia and Skill Learning
- Learning Deficits after Lesions –> Morris water maze
—> rats must swim until they discover a hidden platform in tank
- hippocampal damage: problems finding platform when knew before where it is
- basal ganglia lesion: only remembered where door with reward was (spatial map of hippocampus
Brain Substrates
- Basal Ganglia and Skill Learning
- Neural Activity during Perceptual-Motor Skill Learning
—> BG contribute to learning of perceptual-motor skills
- rats in T-maze
Brain Substrates
- Basal Ganglia and Skill Learning
- Brain Activity during Cognitive Skill Learning
—> BG contribute to cognitive learning
- humans in scanner performing cognitive tasks: BG active
Brain Substrates
- Cortical Representations of Skills
- Cortical Expansion / Reorganization
- regions of cerebral cortex involved in performing particular skill expand in area with practice
- experience is affecting cortical circuits
- practice can change amount of cortical gray matter
- fast learning: select & plan where
- slow learning: actual cortical reorganization
- musicians dystonia —> when one area becomes too big
Brain Substrates
- Cortical Representations of Skills
- Storage of Skill Memories
- structural changes in cortex —> reflect enhancement of skill memories during later stages of training
- transfer specificity —> fast learning: activity; slow learning: only here if critical changes occur
Brain Substrates
- Cerebellum and Timing
- involved in:
- encoding and retrieving skill memories
- forming memories for skills
—> cerebellum most critical for timing
Clinical Perspectives
- Apraxia
- can affect abilities to perform both perceptual-motor skills and cognitive skills —> more about cognitive skills
- hypothesis: they can no longer access memories of certain actions
- treatments: behavioral training that involves extensive repetitive practice
Clinical Perspectives
- Huntington’s Disease
- inherited disorder
- causes gradual damage to neurons throughout brain
- symptoms:
- range of psychological problems
- gradual loss of motor abilities
- facial twitching signals onset
- number of memory deficits
- can learn new perceptual-motor and cognitive skills (but more slowly)
Clinical Perspectives
- Parkinson’s Disease
- symptoms:
- impaired at initiating movements
- harder to learn certain perceptual-motor tasks
- treatments:
- drug therapies
- surgical procedures
- deep brain stimulation
Historical Paper - Karni & Sagi
- latent phase of several hours (8 hours) —> during which perceptual skill evolves
- transference only for fast learning, not for slow
- consolidation —> mostly during sleeping
