Perception

Question 1

SENSORY PROCESSING -

Answer 1

interpreting information our senses receive from the environment

Question 2

Human’s brain have a limited capacity! true or false?

Answer 2

true

Even without a limited capacity it would not make sense to be constantly aware of irrelevant sensory information

Question 3

Vision is interpretive –

Answer 3

brain interprets the visual input.

Question 4

Vision is constructive –

Answer 4

brain constructs representations of the world around us.

Question 5

Our sensory impressions are influenced by:

Answer 5

the contexts in which they take place
our emotional states
our past experiences

Question 6

How do we construct the image we have in our mind?

Answer 6

Making eye movements

Question 7

The retina:

Two types of photoreceptors:

Answer 7

cones (color sensitive, important for colored daylight vision; densely packed in fovea)
rods (important for night vision; vision in the dark is black & white)

Question 8

Retinal ganglion cells-

Answer 8

group of retinal neurons with axons that give rise to the optic nerve

Question 9

Our vision is ‘binocular’ for the middle field?

Answer 9

true

Question 10

The visual information leaves both eyes via the optic nerve?

Answer 10

true

Question 11

Information from each eye crosses over in optic chiasm and goes to the opposite hemisphere

Answer 11

true

Question 12

Visual information goes through the Lateral Geniculate Nucleus (LGN)?

Answer 12

True

Question 13

LGN directs visual information into the visual cortex in the brain

Answer 13

true

Question 14

Vision is HIERARCHICAL
Brain starts by processing most simple properties and works its way up as processing continues
State the stages…

Answer 14

Dots – Lines – Edges – Objects – Movement..

Question 15

Vision is MODULAR

Specific areas of the brain deal with specific information. E.g….?

Answer 15

colours, movement, position…

Question 16

V1 =

Answer 16

PRIMARY VISUAL CORTEX (also Striate Cortex)

Question 17

Left V1 contains a retinotopic map of the entire right visual field, while right V1 contains a map of the…

Answer 17

left visual field.

Question 18

Loss of V1 =

Answer 18

cortical blindness

Question 19

Damage to parts of V1 =

Answer 19

blindness in related part of visual field

Question 20

Blindsightis the ability of people who are cortically blind due to…

Answer 20

lesions in their primary visual cortex (V1) to respond to visual stimuli that they do not consciously see.

Question 21

Area V4 is especially important for…

Answer 21

color perception, and some neurons in V4 respond well to more complex features or combination of features.

Question 22

V4 neurons are sensitive to…

Answer 22

curvature or to two lines that meet at a specific angle.

Question 23

Damage to both V4s can lead to loss of…

Answer 23

colour vision

Inability to identify or discriminate colour

Question 24

Damage to V4 in only one hemisphere can result in a loss of…

Answer 24

color perception to one side of visual space.

Question 25

``` Area MT (V5) The middle-temporal -- MT -- area is important for... ```

Answer 25

motion perception. Almost all neurons in area MT are direction-selective, meaning that they respond selectively to a certain range of motion directions and not to others.

Question 26

The fusiform face area (FFA)...

Answer 26

that responds more strongly to faces than to just about any other category of objects.

Question 27

The lateral occipital complex (LOC)...

Answer 27

has a role in object recognition and responds strongly to a variety of shapes and objects.

Question 28

The parahippocampal place area (PPA)is another strongly category-selective region that responds best to...

Answer 28

houses, landmarks, and indoor and outdoor scenes. This area responds more weakly to other types of stimuli such as faces, bodies, or inanimate objects.

Question 29

Dorsal pathway leading from V1 to the parietal lobe that is important for...

Answer 29

representing ’where’ things are

Question 30

Ventral pathway leading from V1 to the temporal lobe that is important for representing...

Answer 30

‘what‘ objects are. Ventral system includes visual association areas

Question 31

Prosopagnosia is agnosia for...

Answer 31

faces Sometimes called ‘face blindness’ Can be caused by brain damage to FFA or some people have milder version from birth…

Question 32

Agnosia =

Answer 32

‘failure to know’ Impairment of visual perception due to brain damage, which is not attributable to sensory impairment or gross intellectual impairment

Question 33

Visual Agnosia

Answer 33

Patients can no longer identify by sight even simple objects Patients do not have problems with memory for the word Patients do not have with language needed to say the word

Question 34

Lissauer (1890) distinguished:

Answer 34

Apperceptive Visual Agnosia - Patients do not gather elements together to make a ‘whole’. Vision groups elements together (individual lines, colours etc...) to interpret shapes and objects – this ability is lost Associative Visual Agnosia -Patients can ‘perceive’ the object – but can’t name it; they no longer associate it with the correct name. Recognition by touch and verbal description good

Question 35

Visual agnosia – famous case

Answer 35

Patient HJA (Humphreys and Riddoch, 1987) ``` This patient has elements of both ‘apperceptive’ and ‘associative’ agnosias Unable to integrate – in order to make sense of it Can copy (in 6 hours!) but not name ```

Question 36

HJA – Object Decision Task | Study conclusion:

Answer 36

Visual perception has 2 important stages Establishing overall GLOBAL form of stimulus Process that BINDS all the features of a stimulus together

Question 37

Sensory information that refer to the same aspect of the physical world are perceived by differerent senses true or false

Answer 37

true

Question 38

exlain Cross-modal correspondences

Answer 38

mappings between dimensions of a stimulus in different sensory modalities these mappings induce compability effect between that dimensions of a stimulus

Question 39

2 KEY features of cross-modal correspondences

Answer 39

Polarity (stimulus is experienced as „more than”, „less than” another stimulus) Universality (all or most individuals share the same pattern of correspondences)

Question 40

Cross-modal audio-visual correspondences alter:

Answer 40

Speed of information processing Cross-modal associations can modulate audiovisual integration at perceptual level

Question 41

Speed of information processing | explain Pitch VS shape/brightness (MARKS, 1987)

Answer 41

Upturned “V-shape” and upturned “U-shape” was presented with low or high pitched tone. Visual stimuli varied either in brightness (dim vs bright) or angularity (low vs high)

Question 42

Cross-modal correspondences can modulate PERCEPTION OF audiovisual Information true or false

Answer 42

true | what our eyes see can influence what we hear

Question 43

Proposed steps in creating cross-modal correspondences

Answer 43

1. structural regularities of an environment are first to create cross-modal correspondences 2. then they shape vocabulary used 3. with time brain may develop mechanisms to process these cross-sensory mappings (effects of experience on brain’s function and structure)

Question 44

How does the brain integrate auditory and visual information?

Answer 44

Multisensory (supramodal) neurons activation Feedback projections from multisensory areas to sensory-specific areas provide a way for information from one sensory modality (e.g. vision) to inform another sensory modality (e.g., audition) (e.g. Bologini and Maravita, 2007). Stimulation in one sensory modality can also activate brain regions that are specific for different modality via direct anatomical connections between sensory specific brain areas (e.g. Bologini et al., 2010)

Question 45

Important brain areas for multisensory interactions

Answer 45

``` Subcortical Superior colliculus Neurons respond to multiple sensory modalities (supramodal neurons) ``` Cortical Temporo-parietal junction

Question 46

synesthesia key features

Answer 46

``` Syn (join) +aesthesia (feeling) Blending of senses Is involuntary Pairings are relatively stable over life-time Idiosyncratic ```

Question 47

Two main types of mechanisms have been proposed for Synaesthesia:

Answer 47

Hyperconnectivity – there are extra connections in the brain Disinhibition (at the neural level) – reduction in inhibition of brain areas, resulting in lower threshold for activation