H exam I H motor strategies H mate calling in crickets H song production by  s H song recognition by  s H sender-receiver matching H summary PART 3: MOTOR STRATEGIES #11: MATE CALLING IN CRICKETS I

SENSORY INPUT MOTOR OUTPUT VISION OLFACTION GUSTATION AUDITION MOTIVATION COURT FORAGE ATTACK ESCAPE FREEZE CENTRAL INTEGRATION MOTOR STRATEGIES

SENSORY INPUT MOTOR OUTPUT VISION OLFACTION GUSTATION AUDITION MOTIVATION COURT FORAGE ATTACK ESCAPE FREEZE CENTRAL INTEGRATION MOTOR STRATEGIES

SENSORY INPUT MOTOR OUTPUT VISION OLFACTION GUSTATION AUDITION MOTIVATION COURT FORAGE ATTACK ESCAPE FREEZE CENTRAL INTEGRATION MOTOR STRATEGIES

H complex activity, requires H eg, coordinated operation of limbs H often rapid & appropriate responses to environmental signals H sensory-motor interface... behavior itself changes requirements of subsequent behavior MOTOR STRATEGIES

H song production by  s only... H innate recognition by  s... H innate attraction by  s H  s navigate   s... courtship H stereotypic song H many species... many different songs MATE CALLING IN CRICKETS

H ~ 2600 modern cricket species H most work on 3 related temperate latitude families: H bush crickets (Tettigoniidae) H field crickets (Gryllidae) H mole crickets (Gryllotalpidae) H most nocturnal H high predation... many predators, avoid by H hiding, freezing, burrowing, fleeing, camouflage H short calls ~ ventriloquism... hard to locate MATE CALLING IN CRICKETS

H song production in  s by scraping wings together H several types of song H calling song H courtship song H aggressive song MATE CALLING IN CRICKETS

H song production in  s by scraping wings together H several types of song H calling song H  response   = positive phonotaxis H call & remain stationary... attract single  H call & move... attract many  s H amplify & direct call using hollow trees, burrows H courtship song H aggressive song MATE CALLING IN CRICKETS

H song production in  s by scraping wings together H several types of song H calling song H courtship song H 1 of many signals (olfactory, visual, tactile) H aggressive song MATE CALLING IN CRICKETS

H song production in  s by scraping wings together H several types of song H calling song H courtship song H aggressive song H establish territory H threaten impending aggression MATE CALLING IN CRICKETS

H several types of song H 1 st …how NOT to study cricket songs… H calling song… H courtship song H aggressive song… H establish territory H threaten impending aggression MATE CALLING IN CRICKETS

H calling by wing scissor motion = stridulation H file & scraper on wings H sound ~ comb H chirps & syllables H sonogram... amplify... SONG PRODUCTION BY  s

H  oscillogram H cycles H carrier frequency H 5 kHz H 1 scraper tooth H pulses H = syllables H 1 stridulation H chirps & trills H sequences SONG PRODUCTION BY  s

H cricket CNS H chain of ganglia = functional aggregates of neurons H linked by paired connectives H brain (3 fused) H sensory input H subeosphageal ganglion H thoracic ganglia (3) H abdominal ganglia (?) HEAD SONG PRODUCTION BY  s

H meso- & metathoracic ganglia H motor neurons innervate H wing elevator muscles H wing depressor muscles SONG PRODUCTION CIRCUITRY

H meso- & metathoracic ganglia H motor neurons innervate H wing elevator muscles H wing depressor muscles H observe a coordinated sequence of events… H record from H motoneuron H muscle... EMG H electromyogram SONG PRODUCTION CIRCUITRY

H correlate with H tegmen movement H muscle contraction H sound... closing only H note timing of events H oscillating pattern H reciprocal output to antagonistic muscles H typical rhythmic motor activity... eg,walking SONG PRODUCTION CIRCUITRY

H interneuron spikes H motoneuron spikes H thoracic ganglia contain central pattern generator H inhibition (C) H activity (B) H correlate H calls (A) SONG PRODUCTION CIRCUITRY

H central pattern generator (CPG)  call “machinery” H brain  call “decision”... from 3 experiments: H focal stimulation in head H  call & courtship songs H stimulate cervical connective (in “neck”) H  call & courtship songs H cut off head... stimulate individual neurons in cervical connective... H  call, courtship & aggression H single neurons encode each type of trigger TRIGGERING A SONG

H central pattern generator (CPG)  call “machinery” H brain  call “decision” H signals not ~ timing of calls, only onset TRIGGERING A SONG

H brain / cervical connective stimulation shows that behavior onset but not pattern timing ~ stimulation H descending signals need patterning from CPG 2. stimulus freq. ~ rate of chirping H only rate encoded by brain 3. stimulus freq. or strength   transition from call  courtship or aggression H weakest trigger  call TRIGGERING A SONG

H brain / cervical connective stimulation shows that duration of brain stimulus ~ duration of call H constant brain stimulus required for call 5. some stimulation  call suppression... stimulus off  resumed calling more intense, often  courtship, postinhibitory rebound H ~ song  courtship in nature TRIGGERING A SONG

H  song &  response studied for > 200 yrs H how do  s H recognize song ? H navigate   s... phonotaxis ? H can test for hrs H distance constant H  never  “  ” H many versions of device... different questions SONG RECOGNITION BY  s

H  walks toward artificial call H zigzag pattern H oscillations 60° ~ direct line to source SONG RECOGNITION BY  s

H what song features attract  s ? H computer-constructed songs played   s H varied components H syllable rate H syllable duration H chirp rate H # syllables / chirp H duty cycle / chirp SONG RECOGNITION BY  s

H what song features attract  s ? H computer-constructed songs played   s H varied components H syllable rate H 30 / s H others not critical SONG RECOGNITION BY  s

H how does the  H first recognize the song ? H localize the song ? H 2 tympanic membranes H ~ 60 auditory receptor cells H auditory neurons  H auditory nerve  CNS (prothoracic ganglion) H associated with trachea H ears on forelegs SONG RECOGNITION & LOCALIZATION

H tracheal tubes = insect “lungs” H connect tympanum  outside via spiracles H sound via 2 routes H direct H indirect H distance  ½ wave H pull / push SONG RECOGNITION & LOCALIZATION

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