Perception and attention
Errors and Accidents
- Mostly look to the visual area as this is the one we use the most to understand our
world
- How we perceive the environment and how there can be errors and how these lead
to accidents.
Sensation
- Are the 5 senses all we have?
• When you close your eyes, then stretch out your arms. How do you know where
they are?
• If you then wiggle your fingers. How do you know they are moving?
• If you do it all again while standing on one leg will you fall over?
• Which senses allow us to manage this task?
• (sight, sound, taste, smell or touch?)
- Are the 5 all we have? Looking at this task shows us that go beyond the 5 sense
meaning there are more
- We could also classify senses by the nature of the stimulus
- Chemical (taste, smell)
- Mechanical (touch, hearing)
- Light (vision)
How does the brain process these?
- Synaesthesia – eg., experiencing sounds, letters, numbers or words as colours
We could also define a "sense" as a system consisting of a specialised cell type responding
to a specific signal and reporting to a particular part of the brain.
- Taste can be seen as many senses (sweet, salt, sour, bitter)
- Vision can be seen as one sense (light), two (light and color) or four (light, red, green,
and blue….
We can sense:
- temperature,
- pressure,
- touch,
- joint position (proprioception),
- body movement (kinaesthesis),
- balance
- feelings associated with a full bladder, an empty stomach or thirst.
- We also have other monitoring systems we might not be aware of (eg., sensing the
pH of csf)
, - We can also lose high-frequency hearing without losing low-frequency acuity, and
vice versa. (Use frequencies to have younger children not be in certain areas)
Should we think of these as separate senses?
- The more we study the structure of our sense organs, the more senses we appear to
have.
- All these senses can be disabled (e.g., losing the sense of perception, can cause one
to lose ability to be aware of where the body needs to be therefore unable to walk
etc even when the muscles are unaffected)
Perception
- Sensation alone isn't really all that important. Perception is a higher cognitive
process
- Sensation is passive perception is active
- Our knowledge effects how we perceive our senses
When we talk of senses, what we really mean are feelings or perceptions.
• We see light and shade but perceive objects, spaces and people, and their
positions.
• We hear sounds, but we perceive voices or music or approaching traffic.
• We taste and smell a complex mixture of chemical signals, but we perceive
the mix as ice cream or an orange or a steak.
Perception goes way beyond the mixture of sensations
- Involves memory,
- early experiences
- and higher-level processing.
Eg., In the "cocktail party phenomenon", we ignore all extraneous sounds while taking part
in a conversation, but can quickly switch focus if someone else mentions our name.
Perception frees us from our primitive senses.
- Unlike with more simple animals we are not easily fooled by brightly coloured
flowers, or adversaries who can suddenly swell in size, have markings that look like
eyes or smell of something unrelated
- But we also make mistakes Eg., we don’t realise how big trains are, and therefore
misjudge their speed
, Vision:
Errors and Accidents
- Mostly look to the visual area as this is the one we use the most to understand our
world
- How we perceive the environment and how there can be errors and how these lead
to accidents.
Sensation
- Are the 5 senses all we have?
• When you close your eyes, then stretch out your arms. How do you know where
they are?
• If you then wiggle your fingers. How do you know they are moving?
• If you do it all again while standing on one leg will you fall over?
• Which senses allow us to manage this task?
• (sight, sound, taste, smell or touch?)
- Are the 5 all we have? Looking at this task shows us that go beyond the 5 sense
meaning there are more
- We could also classify senses by the nature of the stimulus
- Chemical (taste, smell)
- Mechanical (touch, hearing)
- Light (vision)
How does the brain process these?
- Synaesthesia – eg., experiencing sounds, letters, numbers or words as colours
We could also define a "sense" as a system consisting of a specialised cell type responding
to a specific signal and reporting to a particular part of the brain.
- Taste can be seen as many senses (sweet, salt, sour, bitter)
- Vision can be seen as one sense (light), two (light and color) or four (light, red, green,
and blue….
We can sense:
- temperature,
- pressure,
- touch,
- joint position (proprioception),
- body movement (kinaesthesis),
- balance
- feelings associated with a full bladder, an empty stomach or thirst.
- We also have other monitoring systems we might not be aware of (eg., sensing the
pH of csf)
, - We can also lose high-frequency hearing without losing low-frequency acuity, and
vice versa. (Use frequencies to have younger children not be in certain areas)
Should we think of these as separate senses?
- The more we study the structure of our sense organs, the more senses we appear to
have.
- All these senses can be disabled (e.g., losing the sense of perception, can cause one
to lose ability to be aware of where the body needs to be therefore unable to walk
etc even when the muscles are unaffected)
Perception
- Sensation alone isn't really all that important. Perception is a higher cognitive
process
- Sensation is passive perception is active
- Our knowledge effects how we perceive our senses
When we talk of senses, what we really mean are feelings or perceptions.
• We see light and shade but perceive objects, spaces and people, and their
positions.
• We hear sounds, but we perceive voices or music or approaching traffic.
• We taste and smell a complex mixture of chemical signals, but we perceive
the mix as ice cream or an orange or a steak.
Perception goes way beyond the mixture of sensations
- Involves memory,
- early experiences
- and higher-level processing.
Eg., In the "cocktail party phenomenon", we ignore all extraneous sounds while taking part
in a conversation, but can quickly switch focus if someone else mentions our name.
Perception frees us from our primitive senses.
- Unlike with more simple animals we are not easily fooled by brightly coloured
flowers, or adversaries who can suddenly swell in size, have markings that look like
eyes or smell of something unrelated
- But we also make mistakes Eg., we don’t realise how big trains are, and therefore
misjudge their speed
, Vision:
