Sensory Worlds: The neural basis of animal behaviour. Dr. Katie Lucas Learning in Retirement Winter 2018

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1 Sensory Worlds: The neural basis of animal behaviour Dr. Katie Lucas Learning in Retirement Winter 2018

2 The Field of Neuroethology The neural basis of natural adaptive behaviour Environmental Signal Stimulus Animal Behaviour

3 Neuroethology Stimulus Animal Behaviour Stimulus Neural signal

4 Origins of neuroethology Neurobiology Anaesthetized animals Isolated tissues/cells Ethology Whole animal approach Natural conditions Neuroethology Natural, biologically- relevant behaviours Sensory environment Simple behaviours Lab and field

5 The neuroethological approach Well- defined and quantifiable behaviours (ethology) Accessible neural system

6 Animals' nervous systems have evolved to address problems of sensing and acting in certain environments Their nervous systems are best understood in the context of the problems they have evolved to solve Krough s principle: Study animals that are specialists in the behaviour of interest

7 Neuroethology basic principles Quantifying natural behaviours Sign stimuli Stereotyped behaviours; fixed- action patterns Behavioural state Communication

Nikolas Tinbergen Karl von Frisch 1973 - Achievements in

8 Ethology Analysis of natural behaviour Pioneers of ethology: Provided a conceptual framework for new field Konrad Lorenz Nikolas Tinbergen Karl von Frisch Achievements in comparative behavioral physiology and pioneering work in communication between insects

9 Sign stimuli and behaviour Stimulus Animal Behaviour Sign stimulus: the component of the environment that triggers a specific behaviour Sensory system Sensory filter

10 Sensory filtering Umwelt Sensory World The environment that is perceived after sensory and central filtering For example: Human visual spectrum

11 Sensory filtering Umwelt Sensory World The environment that is perceived after sensory and central filtering For example: Human visual spectrum vs. bee vision Honey guides

12 Sign stimuli and releasing mechanisms Releasing mechanism acts as the filter through which the sign stimulus is processed Acts as the link between the stimulus and the resultant behaviour Example: Egg retrieval in the greylag goose Stimulus Animal Behaviour

13 Sign stimuli and releasing mechanisms Releasing mechanism act as the filter through which the sign stimulus is processed Acts as the link between the stimulus and the resultant behaviour Example: Egg retrieval in the greylag goose

14 Egg- retrieval behaviour in the Graylag goose Fixed- action pattern (FAP) Stereotyped behaviour (motor program) that once elicited, runs to completion without further sensory input

15 Fixed- action pattern 1. It is innate 2. Chains together stereotypic motor sequences 3. Once triggered, runs to completion without need of sensory feedback Carew Fig. 1.1 Sign Stimulus The component of the environment that triggers a specific behaviour ( eggness ) Innate releasing mechanism filter for processing the sign stimuli and triggering the FAP

adult herring gull lowers its head and moves its beak.

16 Releasing value Ability of a stimulus to elicit a species- typical behaviour Dummy stimuli experiments Systematically vary stimulus The adult herring gull lowers its head and moves its beak. The chick pecks the red spot on the beak, causing the adult to regurgitate. Supernormal stimulus

17 Behavioural state The effect of the sign stimulus depends not only on the stimulus presented, but also on the condition of the recipient Influence of the behavioural state on behaviour production Courtship relative to prey capture in male jumping spiders 2- legged model 5o Fig. 3.9 Zupanc

18 Behavioural state The effect of the sign stimulus depends not only on the stimulus presented, but also on the condition of the recipient Influence of the behavioural state on behaviour production 6- legged model Dummy stimulus! 2- legged model 5o Fig. 3.9 Zupanc

19 Communication Sender Signal (Information) Receiver True Communication: The glue that that holds animal societies together Both the sender and the receiver benefit from the information exchange Not just among members of the same species For example, honey guides! Dance language of honey bees (Apis mellifera)

dance Communicates location of food farther away

20 Honey bee communication Round dance Indicates location of food close to the hive (~80 m) Waggle dance Communicates location of food farther away from the hive

21 Honey bee communication Karl von Frisch 1976 The Dance Language and Orientation of Bees Distance: duration of waggle, number of waggles, frequency of sound Direction: direction of run w.r.t. sun

Honey bee communication Artificial dancing bee Dummy stimulus Wing produced sound similar to that generated by dancing bees Recruited worker field bees to fly to

22 Honey bee communication Artificial dancing bee Dummy stimulus Wing produced sound similar to that generated by dancing bees Recruited worker field bees to fly to food dishes they had not previously visited Fig. 2. The mechanical model surrounded by follower bees during the performance of a wagging run. (From Michelsen et al. 1992)

23 Neuroethology summary Quantifying natural behaviours Lorenz, Tinbergen, and von Frisch Sign stimuli Trigger specific behaviour Stereotyped behaviours; fixed- action patterns Greylag goose, herring gull chick Behavioural state Courtship in the jumping spider Communication Dance of the honeybees

24 Neural signals Turning a stimulus into a neural signal What do I mean by a neural signal? They are electrical signals that are transmitted around the body via nerves that make up our nervous system Nerves are made up of collection of nerve cells Nerve cells (or neurons) are the building blocks of the nervous system A typical neuron

25 The Nervous System Peripheral versus Central Nervous system CNS: Brain and Spinal cord PNS: Sends information in and out Bring in sensory information Send out motor information, affect behaviour

26 The Nervous System Peripheral versus Central Nervous system CNS: Brain and Spinal cord PNS: Sends information in and out Bring in sensory information Send out motor information, affect behaviour Pain information sent up through spinal cord to brain Pain receptor (nociceptor)

27 The Nervous System Peripheral versus Central Nervous system CNS: Brain and Spinal cord PNS: Sends information in and out Bring in sensory information Send out motor information, affect behaviour Motor information sent back down from brain through spinal cord Muscle

28 Nerve cells come in all shapes and sizes Pyramidal cell Purkinje cell Basket cell Stellate cell

29 Nerve cells come in all shapes and sizes

30 Brains come in all shapes and sizes

31 Brains come in all shapes and sizes But the fundamental mechanisms remain the same Why we can study the brain of a barn owl, or even a fruit fly, and learn more about ourselves

retina Light Rods and cones are specialized

32 Signal Transduction Turning an environmental stimulus into a neural signal Cross- section of the retina Light Rods and cones are specialized photoreceptors that respond to light by producing an electrical sign

33 Signal Transduction Sensation Receptor Signal Modality Vision Photoreceptor Photons of light Taste Chemoreceptor Chemicals in saliva Smell Chemoreceptor Chemicals in mucus Pain Chemoreceptor Chemicals in fluid Warmth/Cold Thermoreceptor Changes in temperature Sound Mechanoreceptor Sound waves Vibration Mechanoreceptor Pressure

34 Signal Transduction In the natural world, we have to consider other signal modalities (umwelt) Electrical Infrared UV Infrasound

35 Generation of a neural signal

36 The neuron The most fundamental feature of all neurons is the resting potential It is always charged When responding to a stimulus, the potential changes

37 The neuron The most fundamental feature of all neurons is the resting potential It is always charged When responding to a stimulus, the potential changes The movement of charged ions results in a change in voltage

38 Neural signal The dynamic change of the neuron voltage produces an Action Potential All- or- nothing Machine gun Digital information Threshold

39 Turning a neural signal into information

40 Turning a neural signal into information

41 Neural coding Intensity coding Cat pressure receptor Fig. 3.7 (Zupanc)

42 Neural coding - Population code Bear Fig. 9-21

43 Sensory mapping Topographic mapping: the point- to- point mapping of a sensory surface in the brain. Tonotopic mapping in the auditory system Retinotopic mapping in the visual system Somatotopic mapping: the homunculus Somatosensory cortex Bear Fig

44 Somatotopic Mapping (Touch) Bear Fig

45 An example of contact- induced asymmetry in a rat

46 Neuroethology Stimulus Animal Behaviour Stimulus Action potentials

Outline for this course What we know about different

field of neuroethology, with a primer in nerve cells

directional hearing capacity of Barn Owls Lecture 3

fish sense their environment Lecture 5 Learning and

47 Outline for this course What we know about different animal specialists Lecture 1 Introduction to the field of neuroethology, with a primer in nerve cells and animal behaviour Lecture 2 The incredible directional hearing capacity of Barn Owls Lecture 3 Toad visual control Lecture 4 How weakly electric fish sense their environment Lecture 5 Learning and memory in Rats and Bees Lecture 6 Behavioural control by parasites

48 Questions in neuroethology How are stimuli detected by an organism? How are environmental stimuli in the external world represented in the nervous system? How is information about a stimulus acquired, stored and recalled by the nervous system? How is a behavioral pattern encoded by neural networks? How is behavior coordinated and controlled by the nervous system? How can the ontogenetic development of behavior be related to neural mechanisms?

49 How are stimuli detected by an organism? Weakly electric fish RESISTOR* (rocks, plastic rod) * w.r.t. water conductivity CONDUCTOR (most living things, metal rod) Detect changes in self- generated electric field with over electroreceptors along the length of body

50 How are environmental stimuli in the external world represented in the nervous system? Bat echolocation

51 How are environmental stimuli in the external world represented in the nervous system? Bat echolocation Specialized ear Signal processing Periphery and centrally Information source: Amplitude of returning echos Delay Doppler shift Cues bat can discern: Relative velocity of target Flutter of target Range, size, fine characteristics, azimuth and elevation

52 How is information about a stimulus acquired, stored and recalled by the nervous system? Honeybee learning and memory formation Apis mellifera Menzel (2012) Nat. Rev. Virtual Atlas of the HoneyBee Brain: berlin.de/beebrain/

Central Pattern Generator (CPG) Exhibit escape swim behaviour Xenopus

53 How is a behavioral pattern encoded by neural networks? Control of swimming behaviourin tadpoles Simple vertebrate model of a Central Pattern Generator (CPG) Exhibit escape swim behaviour Xenopus laevis Figure 6.3 Zupanc

54 How is behavior coordinated and controlled by the nervous system? Escape in the crayfish Procambarus clarkii Medial Giant interneuron Motor giants Lateral Giant interneuron(s) Tail flip backwards Tail flip upwards/fo rwards Fig. 7.5 Carew (2000) Behav. Neurobiol.

55 How can the ontogenetic development of behavior be related to neural mechanisms? Nottebohm (2005) PLoS Biol Understanding how experience modifies the brain, and interacts with innate aspects Song learning in the Zebra Finch Juvenile birds babble, and over a course of weeks will consolidate song by imitating adult song They will develop degraded but species- typical songs if reared in isolation First proof that neurogenesis occurs in the adult vertebrate brain

Introduction to Neuroscience: Behavioral Neuroscience Lecture 1: Introduction to Animal Behavior

Introduction to Neuroscience: Behavioral Neuroscience Lecture 1: Introduction to Animal Behavior Tali Kimchi Department of Neurobiology Tali.kimchi@weizmann.ac.il Jakob von Uexküll (1864-1944) Umwelt