sensation, perception and consciousness Flashcards
sensation
the physical stimulation of the sensory apparatus (effect of light on the retina, vibrations on ear drum, surface pressure on the skin etc.)
perception
“The process of referring external objects and their causes, from their sensory input, by the mind
“the faculty of perceiving” … “ the ability of the mind to refer sensory information to an external object and its cause”.
the experiential (consciousness) component (what you see, hear, feel, taste, smell) of sensation- “qualia” the distinct sense datum
consciousness
the state of awareness of our own existence, of sensations, of our own thoughts and surroundings
It is a state that is in contrast to being unconscious
vision
LIGHT RECEPTIVE GANGILON CELLS IN THE RETINA
LIGHT is converted to ELECTROMAGNETIC WAVE FORMS
audition
TIMPANIC MEMBRANE (EAR DRUM), ORGAN OF CORTI, HAIR CELLS
CHANGES IN AIR PRESSURE (REVEBERATION/ VIBRATIONS)
somatory sensory/ haptics
(touch)
SKIN – VARIOUS MECHANORECEPTORS
MECHNAICAL PRESSURE/DEFORMATIONS OF THE SKIN, CHANGES ON TEMPERATURE
gaustation
taste
TOUNG – TASTE BUDS IN THE PAPILLAE
CHEMICAL SUBSTANCES DISOLVED IN SALIVA
olfaction
NOSE – CILIA IN THE MUCUS LAYER OF THE EPITHELIUM SITUATATED AT THE TOP OF THE NOSE AND BACK OF THROAT
AIRBOURNE SUBSTANCES DISOLVED IN THE MUCUS LINING
perception is adequate not accurate
– Visual illusions
– Television: Ventriloquist effect
– Also see the McGurk effect
– We don’t sense or process everything we sense, and not everything we process is explicit/conscious even if we respond to it.
why does perception match reality
– Perception is adequate because
- Physical stimuli are rich in information (lots of information out there)
- The human sensory system is really good at gathering information
- Concepts (higher level processes) shape our perception
sensation - detecting
– Information is captured by the sensory systems and converted to neuronal activity
– Information broken down, extracted, analysed and put back together…
– Perception – experiencing
– How we get from sensation to perception is unclear but it seems to be a combination of top down (concepts/expectations) and bottom up processes (structures in the visual pathways)
– Not all of it is explicit and some of it is lost
consciousness level
scale of awareness from zero contents to fully aware
consciousness content
moment to moment here and now experience
low consciousness content
– Low-level: basic here and now (all animals) awareness
high consciousness content
reasoning, self reflecting, ‘I am X’, ‘When I’m older I wan to be Y’ (humans only)
problems with consciousness
where does it come from?
• Consciousness comes from brain activity
• Activity in the brain for stimuli that we process both with and without awareness, and can respond to, is different but present
- How does brain activity actually become conscious awareness? Where does the experience come from?
- Why are we conscious at all?
subjective - measuring when we are conscious?
• Point at which individuals can/can’t report awareness of a stimulus
– e.g. increased brightness of light or sound
objective - measuring when we are conscious?
- Point at which individuals can/can’t make accurate forced-choice decisions about a stimulus or adjust a stimulus (turn up the brightness)
- It’s what we as psychologists measure - Is this awareness or consciousness?
the binding problem
- Consciousness is not unitary it just feels that way
- The binding problem: if incoming information is extracted and broken down to be processed in multiple locations, but how is it then put back together?
Feldman (2013): multiple difficulties.
– If the information has been broken down, and then how is that we see a cohesive whole? How is it put back together?
– How does it remain contiguous (connected) over time?
1. Answer? Some of it isn’t broken down and maybe it doesn’t matter at an unconscious level (see global work space model)
precise synchrony
use timing of single cell firing to time stamp information (problem – computationally expensive)
general synchrony
general pattern of cell firing is used to bind (problem – loss of detail)
weak structural functionalism
Some ‘cells’ do multiple tasks
– The same region of the brain might do more than one job
e.g. pitch/frequency (hi, lo) and timbre (subjective quality)
selective attention
– attentional clusters (grouping)
• We attend (process) things/events together, so they are bound together in the brain
perceptual
– perceiving your environment may help you better interact with it (it might not)
social communication
– understanding and interacting with others (theory of mind)
– What about other animals?
information integration
– Just organised “information”
– Reflect on your own experience
– Allows you to integrate experiences as you have them (but we don’t know why).
the hard problem
How do we become conscious and where does the experience it come from? Are we conscious at all?
soft problem
where does consciousness come from
