Sensation and Perception

Question 1

What is Perception?

Answer 1

Perception is the process by which we interpret and give meaning to sensory information
Perception is an Active Process

Question 2

What is Top-Down Processing?

Answer 2

With Top-Down Processing, the perceptual process starts ‘at the top’ with higher level ‘processing’ in the brain and then works ‘down’ from the whole t o the details. Perception is guided and influenced by cognitive processes, such as drawing on your past experience, knowledge and expectation in order to interpret and assign meaning to raw sensory information.

Question 3

Which Types of Processing fills in gaps in sensory data? (I.e Illusions)

Answer 3

Top down processing will also take account of the context in which perception occurs. If there are gaps in sensory data, then these may be filled in when constructing the perception.

Question 4

What is Bottom-Up Processing?

Answer 4

With Bottom-Up Processing, the perceptual process starts ‘at the bottom’ with raw sensory information that is sent ‘up’ to the brain for higher level mental ‘processing’. Raw sensory data are progressively analyzed at higher and higher levels until they reach the relevant cortical areas in the brain where they are processed and a perception is constructed based on this information. Unlike top-down processing, the bottom-up perceptual process relies ENTIRELY ON SENSORY DATA
aka. Data driven processing

Question 5

What are the three main factors that influence Visual Perception?

Answer 5

Psychological Factors
Biological Factors
Social Factors

Question 6

What are the three stages of Perception?

Answer 6

Selection:
Selection is the process of attending to certain sensory stimuli and excluding others
Involves conscious and unconscious selection

Organization:
Organization is the process of regrouping sensory stimuli to form a meaningful understanding

Interpretation:
Interpretation is the process to which information is given meaning so that it can be understood
Involves bringing together other incoming sensory information and existing knowledge (memories/experiences/emotional state) to make sense of information.

Question 7

What are the three stages of Sensation?

Answer 7

Reception
Reception is the process of detecting incoming accuracy information
The information received by the sensory receptors cannot be interpreted by the brain in its raw form so transduction is required.

Transduction
Transduction is the process by which the information is converted into a form which can travel along neural pathways to the brain as neural impulses
Change the message to an electrochemical message

Transmission
Simply involves sending information to the brain
Once it arrives, the process involved in perception begins
In vision, transmission occurs:
Optic nerve -> Thalamus -> visual cortex

Question 8

How does Transmission occur in Visual Sensation?

Answer 8

In vision, transmission occurs:
Optic nerve detects light -> Thalamus transfers the raw data into electrochemical messages-> the messages begin to be interpreted while they are sent to the visual cortex

Question 9

What is Sensation?

Answer 9

Sensation involves receiving sensory information from the environment

Question 10

Name the 3 Sensory Receptors

Answer 10

Vision: Retina
Hearing: tympanic membrane
Taste: Taste Buds
Touch: Skin, nerves
Smell: Olfactory receptor

Question 11

What are the 3 visual perception principles

Answer 11

The Gestalt Principles
Depth cues
Perceptual consistencies

Question 12

What are the Gestalt Principles? (definition)

Answer 12

The Gestalt Principles are ways in which we organize the visual feature of a scene by grouping them to perceive a whole, complete form.
-In other words these are how the human mind completes a picture without having to actually see the whole picture

Question 13

Name 3 Gestalt Principles (there are more)

Answer 13

Figure ground organization
The Principle of Figure-Ground Organization
We use this principle when we visually organize a scene so that we separate an object (“figure”) from the background
What our eyes focus on is the “figure” and it stands out from the “ground” which is the rest of its surroundings.

Distinction
Contour
Distinctive color
Patterns that obviously differ.

Closure
The principle of closure is the perceptual tendency to close up fill in or ignore gaps in an image in order to view an image in order to view an object as a whole.

Similarity
The principles of similarity is the tendency to perceive parts of a visual image that have similar traits (colors, size, shape, texture) as belonging to together as a group or whole

Proximity
The principle of proximity is the tendency to perceive parts of a visual image which are positioned close together as belonging together in a group

Question 14

What is Depth Perception

Answer 14

Depth Perception is the ability to accurately estimate the distance of objects and therefore perceive the world in three dimensions

Question 15

What are Depth Cues?

Answer 15

Depth Cues are sources of information from the environment (external cues) or from within the body (internal cues) that help us to perceive how far away objects are and therefore to perceive depth
Depth Cues are categorised into two groups - Binocular and monocular

Question 16

What are the 2 Binocular Depth Cues?

Answer 16

Convergence - Detecting the tension in eye muscles as the converge together for closer objects, or apart for objects further away.

Retinal Disparity - The very slight difference (disparity) in the location of the images on the retinas (due to their slightly different angles of view) which enables us to make judgements about the depth or distance of the object

Question 17

Name 4 Monocular depth cues

Answer 17

Accommodation -The detection of the adjustment of the shape of the lens. Depends on relative size of the object (how close it is)

Linear Perspective - The apparent convergence of actual or imagined parallel lines as they recede into the distance (horizon)

Interposition - Also called overlap, occurs when one object partially block or covers another, and the partially blocked object is perceived as further away than the object that obscures it.

Texture Gradient - Refers to the gradual reduction of the detail that occurs on an object or surface as it recedes into the distance, compared with an object or surface that is close and perceived with fine detail

Relative size - refers to the tendency to visually perceive the object that produces the largest image on the retina as closer, and the object that proceeds the smallest image on the retina as being further away

Height in visual field - refers to the location of the objects in our field of vision, whereby objects that are located closer to the horizon are perceived as being more distant than the object that are located further from the horizon.

Question 18

What is Perceptual set?

Answer 18

Perceptual set is a temporary readiness to perceive something in accordance with what we expect it to be.

Question 19

What are 6 factors affecting Perceptual set?

Answer 19

Context - Setting or environment in which a perception is made
Motivation - processes which activate and sustain purposeful or goal directed behavior
Emotional State - How we are feeling when we perceive something
Past experience - Our personal experiences throughout our lives (very important to top-down processing)
Memory (information) - the process of storing and retrieving this perceived information for use
Culture- affects all previous

Question 20

What is Gustatory Perception?

Answer 20

Gustatory perception is our perception of taste.
It is affected by Biological Factors, Psychological factors and Social Factors

Question 21

How do you genetics affect Gustatory Perception?

Answer 21

Roughly 25% of the population are ‘super tasters’ with denser taster buds due to smaller papillae on their tongue. Another 25% are ‘non-tasters’, with larger papillae and less taste buds.

Question 22

How does Age affect Gustatory Perception?

Answer 22

As you grow older. your taste buds slowly die off and cease to be replaced, and your sense of taste lessens. This is why children are so picky, because they have very strong (numerous) taste buds.

Question 23

What are three Biological Factors of Gustatory Perception?

Answer 23

Genetics
Age
Number and regeneration of Taste receptors
Sense of Smell
Physical Health
Hunger
Pregnancy
Arousal
Smoking

Question 24

What are three psychological factors of Gustatory Perception?

Answer 24

Memory
Food packaging and Appearance
Visual perception
perceptual set
Motication
Mood
emotional State
Mental Well being
Attitudes towards healthy eating
Psychological arousal state

Question 25

How is a Taste Aversion formed?

Answer 25

Through Classical Conditioning. If someone associates a particular food with a bad experience, such as nausea, then they may develop a taste aversion

Question 26

What are the three parts of Classical Conditioning?

Answer 26

Neutral Stimulus - Chicken
Unconditioned Stimulus - bacteria
Unconditioned Response - Getting sick

the neutral stimulus now leads to the conditioned response of getting sick