Topic 1: Origins of Brain and Behaviour Flashcards
Brain
Tissue found within the skull
Cerebral cortex
Heavily folded outer layer of the brain tissue
Central nervous system (CNS)
Brain & spinal cord
Peripheral nervous system (PNS)
All the processes that take place beyond the brain & spinal cord
Neurons
Cells in the nervous system
Sensory neuron
Carries incoming info from sensory receptors into the spinal cord and brain
Motor neuron
Carries information from the spinal cord & brain to make muscles contract
2 types of behaviour
- Innate behaviour
2. Learned behaviour
Innate behaviour
Behaviour that is present when we are born
Fixed ways of responding
Learned behaviour
Behaviour that is learned through external forces
Flexible ways of responding
Simpler, smaller nervous system
Narrow range of behaviour (hereditary)
Complex nervous system
Wider range of behaviour (learning)
Historical perspectives on brain & behaviour
Mentalism, dualism, materialism
Mentalism
The explanation of behaviour as a function of the nonmaterial mind (psyche/soul = mind)
Psyche
Responsible for all consciousness, perception, emotions, desires, memories, etc.
Dualism
Both a nonmaterial mind and a material body contribute to behaviour
Mind + body = behaviour
Materialism
Behaviour can be explained as function of the brain and nervous system alone
Nervous system + Brain = Behaviour
Evolution of brains and behaviour
Neurons and muscles -> Nerve net -> Bilateral symmetry -> Segmentation -> Ganglia -> Spinal cord -> True brain
Neurons & muscles
Brain cells and muscles evolved first, allowing animals to move
Nerve net
Simple nervous system, no spinal cord/ brain
Consists of neurons that receive sensory information and connect directly to neurons that move the muscles
Ex. Sea anemone
Bilateral symmetry
Increased organization, one side mirrors the other
Ex. Flatworms
Segmentation
The nervous system has repeating segments
Ex. Vertebrae in humans contain repeating nervous system segments of the spinal cord
Ganglia
Cluster of neurons that resemble primitive brains and function
Ex. Clams & nails
Spinal cord
A single nervous system pathway connects the brain with sensory receptors and muscles
True brain
Specialization/ greater development in areas that are important for that species
Varies according to the behaviour’s level of complexity
Ex. Chordates
Characteristics of nervous systems in chordates
- Bilateral symmetry & segmented
- Brain + spinal cord encased in cartilage/ bone
- Crossed organization ( hemisphere receives info from and controls the opposite side of the body)
- Spinal cord is dorsal to the heart and gut
Cerebrum
Cerebral hemispheres, forebrain
Mirror image hemispheres
Responsible for most conscious behaviour
Cerebellum
Hindbrain
Major brainstem structure specialized in learning & coordination of movement
Principle of proper mass
Species exhibiting more complex behaviours will possess relatively larger brain
(Harry Jerison)
Encephalization quotient (EQ)
Relative brain size obtained from the ratio of actual to expected brain size for an animal of a particular body size
