sensory system tuning (filtering) and organization
DESCRIPTION
Sensory system tuning (filtering) and organization. All sensory systems are designed to extract information from the environment Sensory systems are usually selective Systems tend to focus on a range of what is available Range tends to be restricted to what is “biologically meaningful” - PowerPoint PPT PresentationTRANSCRIPT
Sensory system tuning (filtering) and organization
All sensory systems are designed to extract information from the environmentSensory systems are usually selective
•Systems tend to focus on a range of what is available•Range tends to be restricted to what is “biologically meaningful”•Range is thus “tuned” based on the specificity of the ecological demands
•Tuning tends to have an “optimum” or “best” stimulus •Deviation from this “best” yields less than optimal sensitivity
Keep track of the origin of the tuning curve: it is behavioral or neural data.
Katydid killer auditory tuningParasitoid fly auditory tuning
Optimum sensitivity does not necessarily mean “most meaningful”
VisionOlfaction
Moth olfactory tuning:Concentration response function (receptor neurons) for different odors
Moth olfactory tuning concentration response function (output)
Detection threshold
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Air .0005ug .005ug .05ug .5ug 5ug
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Moth olfactory tuning:Concentration response function (behavioral)
Increased sensitivity usually means increased neural representation in sensory array
Vision
Olfaction
Increased sensitivity usually means increased neural representation in sensory array
Moth olfactory tuningIncreased sensitivity usually means increased neural representation centrally
Male antennal lobe Female antennal lobe
Increased sensitivity usually means increased neural representation centrallyRelative volume of somatosensory cortex devoted to area of skin
Somatotopic integrity: maintains an organized representation
Central organization
Retinotopic integrity of sensory input at the level of primary visual cortex
Chemotopic integrity: maintains an organized representation of receptor type
Chemotopic integrity: maintains an organized representation of receptor type
Types of sensory systems found in nature
1. Chemical senses• Olfaction• Taste
2. Vision 3. Auditory4. Vestibular 5. Somatosensory
• Proprioception• Nociception• Mechanosensation• Thermosensation
6. Magnosensation • Electromagnosensation• Geomagnosensation
7. Geosensation