HCI - THE HUMAN Part 1 Flashcards
2nd PPT
Information is received and responses given via a number of input and output channels
visual channel, auditory channel, haptic channel, movement
Vision begins with ____.
light
it is the primary source of
information for the average person.
visual channel
the ______ in the eye transform it into electrical signals which are passed to the brain
receptors
the ______ and ______ at the front of the eye focus the light into sharp image on the back of the eye, retina.
cornea and lens
what is the 2 types of photoreceptors of the retina?
rods and cones
____ are highly sensitive to light and therefore allow us to see under a low level of illumination.
rods
they are less sensitive to light and can therefore tolerate more light
Cones
retina has specialized nerve cells called ____.
ganglion cells
two types of ganglion cells
X - cells and Y - cells
concentrated in the fovea and are responsible for the early detection of pattern
X - cells
more widely distributed in the retina and are responsible for the early detection of movement
Y - cells
it is affected by both size of the object and its distance from the eye
visual angle
a subjective reaction to level of light
brightness
the amount of light emitted by an object
luminance
it is a function of the luminance of an object and the luminance of its background
contrast
usually regarded as being made up of three components: hues, intensity and saturation
color
brightness of the color
intensity
the amount of whiteness in the colors
saturation
determine by the spectral wavelength of the light. blues have short wavelength, greens medium and red longs
hue
involves the transformation and the interpretation of the complete image, from the light that is thrown onto the retina
visual processing
highlight the differences between the way things are and the way we perceive them
optical illusion
in _____ _____ we need to be aware that we will not always perceive things exactly as they are
interface design
first stage of reading process
First, the visual pattern of the word on the page is perceived
second stage of reading process
It is then decoded with reference to an internal representation of
language.
third stage of reading process
The final stages of language processing include syntactic and semantic
analysis and operate on phrases or sentences
words can be recognized as quickly as
single characters
it is often considered secondary to sight and often underestimated on the amount of information that can be received
hearing
hearing begins with ____
sound waves or vibration in the air
