Lecture 1 - Introduction to the brain part 1

What is behavioural science ?

The field of science that relates BEHAVIOURS to BIOLOGICAL PROCESSES

What are the three tasks all living things face ?

1. Secure energy and essential nutrients

2. Avoid harm and danger

3. Reproduction

What is evolution through natural selection ?

Having new VARIATIONS occur and if the environment favours those variations, they’ll continue to reproduce. (keeping the good, throwing out the bad)

All animals have similar WHAT but have evolved differently to meet their WHAT needs

All animals have similar SKELETONS, MUSCLES and BODY PARTS but have evolved differently to meet their ENVIRONMENTS needs

Evolutionary approach to behaviour

1. WHAT

2. WHAT

Evolutionary approach to behaviour

1. Species-specific behaviours

2. Continuity / conservation of behaviour

What is species-specific behaviour

The natural ACTIONS and RESPONSES shared by nearly all members of a given SPECIES - won’t continue into other species (eg. having a spinal cord, opposable thumbs)

What is the continuity / conservation of behaviour

As the groups become more specific (animals, vertebrate etc) it’s the continuity of a behaviour that will be maintained (eg. eating, hunting)

Traits are passed from WHAT to WHAT

Traits are passed from GENERATION to GENERATION

Traits can WHAT over time to adapt to WHAT (that also changes)

Traits can CHANGE over time to adapt to PARTICULAR ENVIRONMENTS (that also changes)

Evolution and natural selection changes WHAT, but retains the same WHAT

Evolution and natural selection changes TRAITS, but retains the same BASIC PLAN

Neurons are found in all WHAT, and work in the same WHAT

Neurons are found in all ANIMALS, and work in the same BASIC WAY

Neurons are very old WHAT

Adaptations

Darwin and Natural selection:

Based on 3 facts:

1. WHAT

2. WHAT

3. WHAT

and 1 inference:

1. WHAT

Darwin and Natural selection:

Based on 3 facts:

1. Individuals of a given species are NOT IDENTICAL

2. some of this variation can be INHERITED

3. NOT all offspring SURVIVE

and 1 inference:

1. VARIATIONS among individuals affects the probability taht they will SURVIVE, REPRODUCE, and PASS along their CHARACTERISTICS

What did Mendel do ?

Defined the laws of inheritance

Law of inheritance:

Genes come on PAIRS of TWO and are inherited as DISTINCT UNITS, one from each PARENT

What did Hugo de Vries do ?

Described the mechanism of MUTATION that leads to novel traits

What are novel traits ?

NEW or INTRODUCED CHARACTERISTICS in a plant species that are NOT PREVIOUSLY found in its cultivated populations

Traits are passed on through WHAT

DNA

We receive a WHAT of these genes from each WHAT

We receive a COPY of these genes from each PARENT

We have HOW MANY copies of almost every WHAT, except for WHAT

We have 2 copies of almost every GENE, except for GAMETES (eg, sperm and egg cells)

Modern taxonomy:

• Compare WHAT

• Based on WHAT, predict how long ago two species WHAT

Modern taxonomy:

• Compare DNA

• Based on SPONTANEOUS MUTATION RATES, predict how long ago two species DIVERGED (finding the common ancestor)

Nervous system provides means to WHAT, WHAT, WHAT and WHAT external environments

Nervous system provides means to SENSE, REACT, INTERACT and INTERPRET external environments

Darwin’s legacy:

1. If all animals are related, then so must be their WHAT

2. If all animals are related, then so must be their WHAT

3. The nervous system and associated behaviours have been built bit by bit over time from WHAT to WHAT (called WHAT)

If we can study the animal nervous system and behaviour then we can study WHAT

Darwin’s legacy:

1. If all animals are related, then so must be their NERVOUS SYSTEM

2. If all animals are related, then so must be their BEHAVIOURS

3. The nervous system and associated behaviours have been built bit by bit over time from SIMPLE SYSTEMS to COMPLEX ORGANISMS (called EVOLUTION)

If we can study the animal nervous system and behaviour then we can study OUR OWN

The brain’s functional units are WHAT

Neurons

The “Neuron Doctrine”

• Nervous systems are made up of discrete WHAT, WHAT cells: called WHAT

• Neurons contact each other at WHAT: called WHAT

• Together they form the WHAT, WHAT, WHAT and WHAT units of nervous systems

The “Neuron Doctrine”

• Nervous systems are made up of discrete INDIVIDUAL, POLARIZED (nerve) cells: called NEURONS

• Neurons contact each other at SPECIALIZED JUNCTION: called SYNAPSES

• Together they form the DEVELOPMENTAL, FUNCTIONAL, STRUCTURAL and TROPHIC units of nervous systems

What did Anthony van Leeuwenhoek do

Anthony van Leeuwenhoek:

• Postulated that nerves are TUBES containing FLUIDS (spirits) carrying SENSATONS from and to the brain

What did Jan E. Purkinje do

Jan E. Purkinje:

• Identified existence of CELLS in the nervous system

What did Theodor Schwann do

Created the CELL THEORY

What did Augustus Waller do?

Discovered the concept of ANTROGRADE NERVE DEGENERATION

What did B.A. Gudden do

Discovered concept of TROPHIC support. Traced CONNECTIONS between the MAIN CENTERS of the brain

What did Albrecht von Kolliker do

Supplied proof that NERVE FIBRES are CONTINUOUS with NERVE CELLS

What are the two innovations leading to the Neuron Doctrine

1. Microscopy

2. Golgi stain

What was imperfect about the Golgi stain

it showed neurons but NOT ALL neurons

The neuron is a fundamental WHAT, WHAT, WHAT and WHAT unit for the nervous system

The neuron is a fundamental STRUCTURAL, DEVELOPMENTAL, FUNCTIONAL and METABOLIC unit for the nervous system

Neurons are WHAT cell which are NOT WHAT with other cells

Neurons are DISCRETE cell which are NOT CONTINUOUS with other cells

The neuron is composed of 3 parts:

The dendrites (receive info), a single axon and a cell body

Information flows along the neuron in WHAT direction (from WHAT to the WHAT via the WHAT)

Information flows along the neuron in ONE direction (from DENDRITES to the AXON via the CELL BODY)

What is a SYNAPSE

A barrier to TRANSMISSION exists at the site of CONTACT between two neurons that may permit a TRANSMISSION

What is a unity of transmission

Synaptic contacts between two cels can be either INHIBITORY or EXCITATORY, but will always be the same type

What does an inhibitory do

Decreases the likelihood of a receiving neuron firing an action potential

What does an excitatory do

Increase the probability of a neuron firing an action potential

What is Dale’s law

Each nerve terminal releases a SINGLE type of TRANSMITTER (ex: dopamine, serotonin, but that transmitter will only release that specific one)