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Review of recent findings in cognitive neuroscience and
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A COGNITIVE NEUROSCIENCE PERSPECTIVE ON MEMORY FOR PROGRAMMING TASKS
Chris Parnin, Georgia Institute of Technology
In the year 2042, super programmers strapped in SQUIDs (superconducting
quantum interference devices) build programs to save the earth from certain doom.
SQUID SOUND LIKESCIENCE FICTION?
NO!!
These devices exist right now -- just
waiting to be used!
COGNITIVE NEUROSCIENCE
Understanding how the functions of the physical
brain can yield the thoughts and ideas of an intangible
mind.George Miller and Michael Gazzaniga
Benefits?
Image no more keyboards.
Direct measures of function and understanding.
Better predictions and constraints from models.
COGNITIVE NEUROSCIENCE
BackgroundAnatomy,
techniques, findings with focus
on memory
InsightsInsights from
models old and new
ImpactTools, theories, experiments
OVERVIEW
LOBES
Frontal Parietal
OccipitalMedial
Regions divided by deep fissures
LIMBIC SYSTEM
Deep structures within brain.
FUNCTION LOCALIZATION
HUMAN TECHNIQUES
Electro/magno-basedMeasures change in neuron activity
Affects visible within milliseconds.
Location within centimeters.
Examples• EEG• MEG
Blood oxygen-basedMeasures change in blood activity.
Affects visible within seconds.
Location within millimeters.
Examples• fMRI• Optical imaging
ANIMAL TECHNIQUES
Gene TherapyBred mutant rats
DyeDiscover neural pathways
LesionsDamage neural pathways
HabitationThe kitten who only saw vertical lines
Cats, Monkeys, Mice Oh My!
Stimulate neurons with electricity
LONG-TERM POTENTIATION (LTP)
Effect found even after one year!
PLACE CELLS
VIRTUAL NAVIGATION
Participants navigate a virtual town.
Recall paths.
Place cells fire.
NEUROGENESIS
Larger volume by years of experience!
Size of taxi driver hippocampus?
HIPPOCAMPAL ACTIVITY
Forgotten words Remembered words
Forgotten words Familiar words
(Entorhinal cortex)
AUTOMATIC MEMORY
We cannot anticipate important events.We cannot always devote top-down resources to encode and select memory.
Initial memory is largely formed without conscious effort.
HIPPOCAMPUS ANATOMY
Grand Central of the sensesConnections to sensory processing and semantic recognition. Connections to frontal regions.
Brain HashtableHippocampal neurons cannot store directly, index to original source.
Recording factorsNovel, engaging, high-frequency…
SNOWBALL TO BOULDER
Hippocampal LTP
Formed and tagged for storage.
Consolidated memory
Replayed and stored at original regions.
Top-down associations
Properties our bound to memory. “Rehearsal” is activation of speech motor.
INSIGHT
So what?
A review, and new perspectives.
Sensory Short-term Long-termAttention Encoding
Rehearsal
MODAL MODEL OF MEMORY(1968)
Patients with no short-term memory still have long-term memory…
Sensory Short-term Long-term
EpisodicBuffer (2000)
Lifetime of seconds!
“Temporarily infinite”
WORKING MEMORY (1974)Phonologica
l loop
Visio-Spatial Sketch pad
Central Executiv
e
LONG-TERM WORKING MEMORY(1995)
Good insight, theory formed without any neuroscience basis.
MEMORY 2.0
• Distributed• Specialized• Retained and Replayed• Automatic without Rehearsal• Immediate and Long-Lasting
MEMORY TYPES
SpatialProspectiveFamiliarityRecencySource
Semantic…
See paper for more details!
AttentionMaintenanceManipulation
Dynamic filtering
Auto associative
retrieval
Auto associative encoding
Retrieval Encoding
TASK MEMORY MODEL (beta)
Semantic Se
man
tic
Indices
Spatial
Goals
Attention
Bindings
Visual
Frontal
Associative
Perceptual
ProcessRegions
Note, top-down iteration is a “brain design-pattern” found in many neural circuits.
PROGRAMMING ENVIRONMENTS
Often do not associate name with memories of programming.
NAME IS NOT ENOUGH
TOOL DESIGN: MEMORY
• Auto-association– Better distinct cues for learning?
• Spatial memory?– Spatial stability, isolation
• Prospective memory?– Better reminders than a compile error or TODO?
• Forgetting?– Code history and provenance
THEORIES (BETA)
Visual Chunks
Initial formation of memory.“Below the method with
lots of strings”
Iterative Comprehension
Top-down experiences will bind and update partial
representations. Concepts form.
Navigational Jitter
Tabs, scrolling huge files,
little understanding-- need memory aids.
EXPERIMENTS
Gender differences in brain activity during programming?
Neurogenesis in programmer’s brain?
Place cells (spatial) during programming navigation?
Your idea?
MUSCLES OF THE MIND
+ =
Subvocal speech
EMG (electromyograph
y)Cognition
0 100 200 300 400 500 600 700 800 900
Subvocal Debug
Select Click
Search Edit
FormulatingProblem
Found useful code
Formulatingsolution
EditingFound useful code
Evaluating
Moments of interest and difficulty
QUESTIONS?
Indices
Spatial
Goals
Attention
Bindings
Visual
Goal Memoryspace-goal binding.
Lesioned monkeysForget food location.
VariationChange location, keep consistent cue