Download Lesson1 Powerpoint

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project

Document related concepts

Development of the nervous system wikipedia , lookup

Neuroscience in space wikipedia , lookup

Neuroplasticity wikipedia , lookup

Visual selective attention in dementia wikipedia , lookup

Executive functions wikipedia , lookup

Central pattern generator wikipedia , lookup

Convolutional neural network wikipedia , lookup

Premovement neuronal activity wikipedia , lookup

Neuroethology wikipedia , lookup

Sound localization wikipedia , lookup

Cortical cooling wikipedia , lookup

Endocannabinoid system wikipedia , lookup

Activity-dependent plasticity wikipedia , lookup

Neuroesthetics wikipedia , lookup

Response priming wikipedia , lookup

Sensory cue wikipedia , lookup

Time perception wikipedia , lookup

Rheobase wikipedia , lookup

Visual extinction wikipedia , lookup

Signal transduction wikipedia , lookup

Perception wikipedia , lookup

Neural coding wikipedia , lookup

Molecular neuroscience wikipedia , lookup

Embodied cognitive science wikipedia , lookup

Sensory substitution wikipedia , lookup

Clinical neurochemistry wikipedia , lookup

Perception of infrasound wikipedia , lookup

Neuropsychopharmacology wikipedia , lookup

Psychophysics wikipedia , lookup

Neural correlates of consciousness wikipedia , lookup

Visual N1 wikipedia , lookup

Allochiria wikipedia , lookup

C1 and P1 (neuroscience) wikipedia , lookup

Efficient coding hypothesis wikipedia , lookup

Evoked potential wikipedia , lookup

P200 wikipedia , lookup

Stimulus (physiology) wikipedia , lookup

Feature detection (nervous system) wikipedia , lookup

Transcript
Sensory systems basics
Sensing the external world
Sensory transduction
Transforming
external physical
forces/energy into
electrical impulses
that are mediated
by neural spikes.
Neural “encoding”
Encoding stimulus amplitude
Responses of a
photoreceptor to
light at different
intensities.
Information is
encoded by both
amplitude and
length of the
response.
Encoding stimulus location
The location of the stimulus in
space is encoded by the identity
of responding receptors.
Encoding stimulus location
Encoding stimulus location
Distribution of receptors
Different organs (or organ locations) contain
different amounts and types of receptors.
Distribution of receptors
Distribution of receptors
Sensory pathways
Sensory pathways
Central nervous system
Vision
Topographical organization
Photoreceptors
responding to the
left visual field
innervate the right
LGN.
Topographical organization
Both the thalamus
and early visual
cortices contain
retinotopic maps of
visual space.
Occular dominance
Information from
the left and right
eyes remains
segregated in the
LGN.
Occular dominance
Also in primary visual cortex.
Cortical magnification
Cortical magnification
Acuity
Columnar organization
Selectivity to stimulus attributes
Spatial receptive fields
Contrast
Luminance
Spatial frequency
Orientations
Colors
Movement direction and/or speed
Textures
Shapes
Receptive field
Many visual neurons have
excitatory and inhibitory
parts to their receptive
field.
Examples of retinal and
LGN cells.
Retino-topic mapping
Luminance & Contrast
Orientation selectivity
Orientation selectivity in primary visual cortex.
Orientation selectivity
Pinwheels
(only in primates)
Hierarchy and integration
LGN
V1 Neurons
Invariance and Gain
Contrast invariant
orientation tuning.
Response gain
Contrast
Spatial frequency
Integration
over space.
Spatial frequency
Movement direction
Integration
over time.
Overlapping representations
of orientations and directions
Hierarchy and integration
Low, mid, and high level
vision
Functional specialization
Face selectivity
Invariance (abstractness)
Is this vision or abstract memory?
Audition
Choclear output
Selectivity to specific
frequencies.
Louder stimuli
generate less selective
responses.
Sound localization
Interaural time differences (ITD)
Sound localization
Brainstem areas:
Olivary nuclei
Colliculus
Sound localization
Auditory brainstem response
Tonotopy
But no spatial encoding…
Language system
Lateralized!
Language structure
Phonetics: ‘ba’, ‘da’, ‘pa’
Words, Grammar, Intonation
How is all this encoded?
Language hierarchy?
Invariance across hearing and reading?
Specific white matter tracts
Aphasias
Somatosensation
Parallel pathways
Parallel pathways
Each pathway
conveys a different
“part” of the
information.
Redundancy…
Topographic organization
Homonculus
Secondary Somatosensory areas
How does all this develop?
Genetics
Experience
Flexibility/Plasticity