Cognition Chapter 2 (Perception) Flashcards
What is perception
Perception is our own (subjective) sensory experience of the world.
It is more than just a pure registration of the physical world
Explain sensation and cognition
Perception is made up from sensation and cognition
Sensation is the transformation from energy to brain signals
Cognition is the use of mental representations (not always truthful)
*How is cognitive psychology and the developments of robots connected
The human perception system is the best there is. It has therefore become the primary model for robots, and learning how humans percieve and work can be translated into robots and softwares.
Explain the inverse problem
It is a fundamental concept of perception
It describes why even fr the best sensory organs perception cannot typically guarantee a faithful representation of the physical world.
It is basically that there are wrong perceptions for our enviroment
Explain the likelyhood principle and its two subprinciples
It is a fundamental concept of perception.
The way an object is perceived will be the one which is most
likely.
2 Principles
1. Prior probability (How much we expect the perception BEFORE percieving)
2. Likelihood (uncertainty of perception)
Explain the bottom up and top down principle
Bottom up means that perception is just a pure transformation from sensory data into a perception (seeing the skin and shape of an orange)
Top down processing is when this perception is influenced by cognitive factors like knowledge and expectation (Seeing an orange in a bowl full of fruit)
Quickly explain the parts of the perceptual system
The perceptual system is the system with which we percieve
It consists of the 5 senses (visual, auditory, sematosensory, smelling and tasting), but also of Balance, self perception, pain and warmth perception
Explain the visual system overall and in the eye and 4 important receptors of the eye
The human eye is able to proces wavelength between 400 and 700
- The retina is the skin inside the eye with photoreceptors (convert light into electric signal)
- The fovea is the place on the retina where the image is projected on
- In the retina there are canes (for colour) and rods (for light intensity)
Explain the visual system in the brain in its 4 principles
- visual perception is contralateral (on the opposite site)
- There is retinotopic organisation in the primary visual cortex (the locations match the visual field)
- There are feature detectors (each neuron sensitive for specific feature like shape)
- There is Hierarchic oranisation (simple cells for simple features, complex cells for combination of simple ones, hypercomplex for combination of complex ones)
Explain the 2 streams in the visual system
- Dorsal stream (Up) for spatial information goes trough the pariental lobe.
(Brain damage leads to visual neglect) - Ventral stream (Down) for information about identity goes through the temporal lobe. (Brain damage leads to Visual agnosia and Prospagnosia)
Explain the auditory system and its role in the ear
Input in auditory form is sound, which comes from vibrations and waves (between 20 Hz and 20 kHz)
In the ear the vibrations are sensed by hairs in the basilar membrane which then give out electric signals
The pitch is defined by the location of the hairs in the inner ear (cochlea)
Explain the auditory system in the brain in 3 principles
- Audio is processed in the auditory cortex
- There is Tonotopic organisation (pitches are close to each other)
- Loudness is defined by the firing rate of neurons
Explain the somatosensory system in 4 principles
- Cells in the skin convert pressure to electrical signals
- The signals are processed in the somatosensory cortex
- There is somatotopic organisation (close body parts are close to each other in the brain)
- Sensitive body parts have more neurons
Explain multisensory integration in 3 points
- Combination of sensory information gives us more reliable information (nose plays big role in tasting)
- There are effects like the McGurk effect (hearing s influenced by seeing mouth) and visual capture (visuals dominate over perceptual modalities)
- Synthesia is when there is a unusual mixture of perceptions
Explain the Theory of template matching
It is one of the 4 theories of perception
Every perception is compared with templates stored in memory
Problems: New stimuli should get recognised, templates require too much storage capacity
Explain the theory of Pandemonium Model
It is one of the 4 theories of perception
There are four stages of neural visual processing, which are represented by demons
1. Image demons see light
2. Feature demons recognise specific features
3. Cognitive demons respond to feature demons and make sense of it
4. Decision demon listens to cognitive demons and labels image.
Explain the prototype theory
It is one of the 4 theories of perception
An object is recognized from its resemblance to its best prototype of its category
Explain the Theory of recognition by components
Objects are recognised by constructions of geons
Geons (volumetric primitives) are shapes that can be recognised no matter what perspective we see them
This can be tested by showing images without geons which proves it right
Humans recognise fast by geons at the expense of accuracy
Explain social perception
- Percieving faces and voices is special and have their own brain areas.
- Recognition of biological motion is very easy
- The Capgras syndrom is when a person believes that close people are duplicates, which shows that there are two systems in recognising people (Overt is being able to name and see properties of the face; Covert is being able to react emotionally to the person). Prosopagnosia is the opposite.
