A4 Innate and Learned Behaviour Flashcards
Behaviour
is typically defined as any observable action by a living organisms
Behaviours can be categorised as either innate or learned
Innate behaviour
is an instinctive response that is developmentally fixed – it is independent of environmental context
Innate behaviours have a genetic basis and are hence inherited from parents
Any instinctive response that improves survival and reproductive prospects will become more common by natural selection
Taxis
is a change in movement in response to an environmental stimulus – either towards (positive) or away (negative)
Euglena is a photosynthetic microorganism that requires light as an energy source and hence displays positive phototaxis
Step 1: Place Euglena in a petri dish with appropriate environmental conditions for survival
Step 2: Cover the dish with aluminium foil, excluding a few small exposed sections
Observation: With a light source placed above the dish, the Euglena should migrate towards the exposed sections
Kinesis
is a change in the rate of activity in response to an environmental stimulus
Woodlice have gills for respiration and tend to prefer moist conditions (their gills may dry out in dry conditions)
Step 1: Place a woodlouse in a dry petri dish and mark its movements every 30 seconds
Step 2: Repeat this process for a second woodlouse placed in moist conditions (i.e. petri dish lined with wet paper towel)
Observation: The woodlouse in dry conditions should have a higher rate of movement (improve chances of finding moisture)
Reflexes
responses may be involuntary and occur without conscious thought
do not involve the brain – instead sensory information is directly relayed to motor neurons within the spine
This results in a faster response, but one that does not involve conscious thought or deliberation
Pain reflex arc
A pain stimulus is detected by a receptor (nocireceptor) and a nerve impulse is initiated in a sensory neutron
The sensory neuron enters the spinal cord via the dorsal root and synapses with a relay neuron in the grey matter
The relay neuron synapses with a motor neuron, which leaves the spinal cord via the ventral root
The motor neuron synapses with a muscle (effector), causing it to contract and remove the limb from the pain stimulus
Learned behaviour
is not developmentally fixed and can be modified by experience
Learned behaviour shows significant variation as it is influenced by environmental context
Learning involves acquiring information from past experiences to adapt to new situations
The capacity to learn particular skills may be influenced by genes, but will not develop without appropriate experiences
Learning improves an organism’s survival prospects as they can modify their responses to changing environmental conditions
Imprinting
is any kind of phase-sensitive learning that is rapid and independent of behavioural consequences
Imprinting occurs during a short critical period in which the organism adopts behavioural characteristics from a stimulus
Imprinted behaviour is not influenced by consequences – it does not require reinforcement to develop
Conditioning
is a process of behaviour modification whereby desired behaviours become associated with unrelated stimuli
This process can be achieved via either classical (reflex) conditioning or operant (instrumental) conditioning
Reflex conditioning
involves placing a neutral signal before a reflex in order to create an association between the two
Reflex conditioning focuses on involuntary and autonomic behaviours
It involves associating a desired behaviour with a new stimulus
Pavlov’s Experiment
Reflex conditioning was first described by Ivan Pavlov, a Russian physiologist who experimented on dogs
Dogs normally salivate (unconditioned response) in anticipation of being fed (unconditioned stimulus)
Pavlov sounded a bell (neutral stimulus) prior to feeding a dog
After many repetitions, the dog came to associate the bell with food and began to salivate to the bell (conditioned response)
Pavlov described this as a conditioned reflex – the stimulus that prompted the response had been changed
Operant conditioning
involves applying reinforcement or punishment after a behaviour to increase or reduce its occurrence
Operant conditioning focuses on strengthening or weakening voluntary behaviours
It involves associating a particular behaviour with a specific consequence (either reward or punishment)
Development of birdsong
The development of birdsongs in fledglings is an example of an action that involves both innate and learned behaviours
Birds will use songs as a means of communication – either signalling courtship or establishing territorial boundaries
Most birds are born with a crude template song that is genetically inherited (innate behaviour)
The possession of an innate template prevents birds from adopting the songs of a different species of bird
Whilst young, fledglings learn to expand and refine their song by listening to, and mimicking, the adult version (motor learning)
Birds raised in isolation will lack the necessary song complexity that develops through social interaction
The time taken to develop a birdsong differs between species and songs, but once established, the final song is rarely altered
Memory
is the faculty of the mind by which information is encoded, stored and retrieved
Encoding involves converting information into a form that can be stored (e.g. visual cues, sounds, semantics)
Accessing involves the retrieval of stored information to be actively used in cognitive processes
Information can be stored as a short term memory (short recall duration) or long term memory (indefinite recall period)
Short term memories can be converted to long term via the repetitive recall and consolidation of the information
Information that is not stored as a memory will be forgotten and will have to be re-learned
Many parts of the brain are involved in memory – including the prefrontal cortex and the hippocampus
