Reasoning and the Scientific Method

scientific method

involves both inductive and deductive reasoning

deductive scientific method

if all a are b

and all b are c,

then all a are c

inductive scientific method

• uses specific observations to arrive at broader generalizations or theories, moving from particular instances to general principles

• ex: everyone I know from sweden has blonde hair. our new exchange student comes from sweden, therefore, she probably has blonde hair.

deductive scientific method (wrong)

• everyone from sweden has blonde hair. our new exchange student comes from sweden. therefore, she has blonde hair

mechanical sense

• type of sense

• touch

• hearing

• vestibular

• joint

• muscle

photic sense

• type of sense

• vision

thermal sense

• type of sense

• cold

• warmth

chemical sense

• smell

• taste

• vomeronasal

electrical sense

• type of sense

• electroreception

magnetic sense

• type of sense

• magnetoreception

sensory transduction

• converting energy from a stimulus in the outside world into electrical impulses in a sensory receptor cell

receptive field

• the “sensory space” in which the presence of a stimulus will alter a particular neuron’s firing rate

labeled lines

• different sense organs transmit to specific areas of the brain

  • incoming sensory signals go first to primary area, and then to association areas for further processing

  • the brain needs to determine which are active

how are different stimuli coded?

• taste (gustatory): how is sweet, sour, salty, etc detected?

• smell (olfactory): how is smell of flower, banana, sour milk, detected?

receptor cells in sensory organs

• labeled lines

• combinatorial coding

combinatorial coding

• receptors may respond to a range of stimuli

  • the brain needs to “decode” the input pattern of signals from various odorant receptors

law of continuity

• perception of partial stimuli as whole

  • perception is more than a response to sensory inputs

  • phenomenon of completion shows that we can create things that are not actually there

multisensory integration

• how the brain combines information about each sense

mcgurk effect

• where what you see someone’s mouth doing when they speak influences what you hear