Transcript odor learning & proboscis extention reflex

PART 4: BEHAVIORAL PLASTICITY
#19: ASSOCIATIVE LEARNING IN HONEYBEES II
 exam 2
 learning in a natural environment
 special case... flower learning
 odor learning in the proboscis extension reflex
 summary
PART 4: BEHAVIORAL PLASTICITY
#19: ASSOCIATIVE LEARNING IN HONEYBEES II
 exam 2
 learning in a natural environment
 special case... flower learning
 odor learning in the proboscis extension reflex
 summary
SEMINAR
 Dr. Spence Behmer
 Department of Entomology,
Texas A & M University
 Friday, April 6th @ 3:30
WHI Auditorium
 Grasshoppers and nutritional
physiology:
from learning to community
structure
 to supplement your enjoyment or if you can’t
make the seminar… literature will be posted
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 PER from sucrose contact on proboscis or
antennae
 reliable in hungry bees
 studied in the laboratory
 used with odor for conditioning
 some simple rules for learning...
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 odor by itself does not elicit PER
 classical or Pavlovian conditioning
 US = sucrose
 UR = PER
 CS = odor
 training: US + CS
 test: CR = PER
 bees learn that odor predicts sucrose reward
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 in color experiment
 classical or Pavlovian conditioning
 US = sucrose
 UR = feeding
 CS = color
 training: US + CS
 test: CR =  preference
 bees learn that color predicts sucrose reward
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 CS (e.g., color)
must precede US (sucrose)
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 CS (e.g., pattern) must precede US (e.g., sucrose)
 can use 2 CS stimuli = differential conditioning
 CS+ = paired with US
 training
–
 CS = not paired with US
 CR = shift in preference for either testing
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 CS (e.g., odor) must precede US (e.g., shock)
 can use 2 CS stimuli = differential conditioning
 CS+ = paired with US
 training
–
 CS = not paired with US
 CR = shift in preference for either testing
odor “A” (CS+) + shock (US)
odor “B” (CS–)
flies  choice point
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 CS (e.g., odor) must precede US (e.g., shock)
 timing critical
 determine interstimulus
interval function
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 interstimulus interval function determination in PER
 CS = geraniol odor
 US = sucrose
 optimal response when CS preceeds US by 2-3s
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 interstimulus interval function determination in PER
 similar to color learning in free flying bees
 CS = color
 US = sucrose
 optimal response when CS preceeds US by 2-3s
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 acquisition function determination in PER
 how fast do bees learn?
 CS = odor
 US = sucrose
 asymptotic response with 3 trials
 excitatory or faciliatory conditioning leads to CR 
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 CS as predictor of the absence of US
 how does unpaired CS pre-exposure influence
CR?
 CS = odor
 US = sucrose
 inhibitory conditioning reduces effect of training
ODOR LEARNING & PROBOSCIS EXTENTION REFLEX
 differential conditioning in PER
 can it be reversed?
 CS+ = odor A paired
 CS– = odor B unpaired
 US = sucrose
 1st generalize to odor, then differentiate with
training
 CR+ & CR– are opposite
ANATOMY OF PER
 insect brains ~ vertebrate brains
 fewer neurons
 ~ complexity
ANATOMY OF PER
 insect brains ~ vertebrate brains
 fewer neurons
 ~ complexity
 e.g., Drosophila
ANATOMY OF PER
 insect brains ~ vertebrate brains
 fewer neurons
 ~ complexity
 e.g., Drosophila
 sensory input
ANATOMY OF PER
 insect brains ~ vertebrate brains
 fewer neurons
 ~ complexity
 e.g., Drosophila
 sensory input
 motor output
ANATOMY OF PER
 insect brains ~ vertebrate brains
 fewer neurons
 ~ complexity
 e.g., Drosophila
 sensory input
 motor output
 processing
ANATOMY OF PER
 insect brains ~ vertebrate brains
 fewer neurons
 ~ complexity
 e.g., Drosophila
 sensory input
 motor output
 processing
 neuropile
 cell bodies
ANATOMY OF PER
 honeybee brain
 ~ 106 neurons
 complex
 what neuropiles
mediate PER?
ANATOMY OF PER
 honeybee brain
 ~ 106 neurons
 complex
 what neuropiles
mediate PER?
 CS
ANATOMY OF PER
 honeybee brain
 ~ 106 neurons
 complex
 what neuropiles
mediate PER?
 CS
 US + “VUM”
ANATOMY OF PER
 honeybee brain
 ~ 106 neurons
 complex
 what neuropiles
mediate PER?
 CS
 US
 CS + US convergence?
ANATOMY OF PER
 CS + US convergence?
 3 regions tested using bilateral cooling:
 antennal lobe
 mushroom body -lobe
 mushroom body -lobe
ANATOMY OF PER
 CS + US convergence?
 3 regions tested using bilateral cooling:
 antennal lobe
 mushroom body -lobe
 mushroom body -lobe
ANATOMY OF PER
 CS + US convergence?
 3 regions tested using bilateral cooling:
 antennal lobe
 mushroom body -lobe
 mushroom body -lobe
 distributed function
 MB most critical
ANATOMY OF PER
 CS + US convergence?
 two specific neurons tested for PER functions:
 PE1
 VUMmx1
ANATOMY OF PER
 CS + US convergence?
 PE1
 dye filled
ANATOMY OF PER
 CS + US convergence?
 PE1
 intracellular recordings
 reduced response after training
ANATOMY OF PER
 CS + US convergence?
 PE1
 intracellular recordings
 qualitative change in response with multiple
trials
 may be change in PE1 or change in KC input
ANATOMY OF PER
 CS + US convergence?
 VUMmx1
 ventral unpaired medial
 dye filled
 VERY extensive pattern of arborization
 all areas of CS & US input
ANATOMY OF PER
 CS + US convergence?
 VUMmx1
 intracellular recording
 fires in response to sucrose application
 triggers neural circuit  proboscis extension*
ANATOMY OF PER
 CS + US convergence?
 VUMmx1
 substitute sugar with
injected current
 measurement of PER*
 VUMmx1 provides US
 current alone does  UR
 separates sensory from US
at neural level
ANATOMY OF PER
 CS + US convergence?
 VUMmx1
 intracellular recordings
  spikes with forward
conditioning only
ANATOMY OF PER
 CS + US convergence?
 VUMmx1
 differential conditioning
 intracellular recordings
 responds to CS+ only
ANATOMY OF PER
 CS + US convergence?
 VUMmx1
 1st order conditioning
 train: CS1 (odor A) + US1 (sugar)
 test: CS1  CR1 (PER)
 2nd order conditioning
 train: CS2 (odor B) + CS1 (odor A = US2)
 test: CS2  CR2 (PER = CR1)
ANATOMY OF PER
 CS + US convergence?
 VUMmx1
 octopamine transmitter
 substitute sugar with
octopamine injection @
 calyx
 antennal lobe
 measurement of PER*
 VUMmx1 provides US
LEARNING IN HONEYBEES: SUMMARY
 learning necessary for survival in nature
 several forms of learning
 several modalities of learning
 rapid learning
 permanent memory in 3 trials
 temporal requirements of learning critical
 waggle dance
 integrate stimuli
 can learn complex patterns
 can learn general environmental features
LEARNING IN HONEYBEES: SUMMARY
 proboscis extension reflex (PER)
 show all features of learning described in
vertebrates
 temporal requirements of learning
 differential conditioning
 inhibitory learning
 2nd order conditioning
 structures correlated with learning
 mushroom bodies & antennal lobes
 neurons correlated with learning