Sensation Flashcards
What are the specialized cells embedded in the retina that transduce light into a nerve signal? Where is this signal sent?
Photoreceptors, signal sent to Thalamus
Section at the back of the eye containing no photoreceptors where blood vessels and optic nerve run through. What does having no photoreceptors there cause?
Optic disk, causes a blind spot
How is Sensation defined?
Limited by stimulation
How is perception defined?
Elaborates or builds upon stimulation. Reconstruction of our world, not an exact replica
Influenced by:
Experience, Context, Contradictory information from different senses
What are the monocular depth Cues?
Relative Size
Texture Gradient
Interposition
Linear Perspective
Height in field
Motion parallax
Define: Relative Size
Judging how big/small and object is in relation to past experiences
Define: Texture Gradient
Texture of a surface appears denser and finer as it gets further away
Define: Interposition
One object partially bocks another
Define: Linear Perspective
Meeting of parallel lines at a distant point, resulting in a vanishing point
Define: Height in field
Perceived distance based on vertical position within the visual field
Define: Motion parallax
Objects that are closer appear to move faster than objects that are further away
What is top-down influence on perception?
Influence based on expectations and prior knowledge
When do auditory and visual illusions occur?
When the sensory system is given conflicting cues from the environment about a stimulus
What is the difference between pitch and loudness?
pitch: ears response to frequency of sound
loudness: energy of the wave
What is the Doppler Effect?
Sudden pitch change due to an increase or decrease in the frequency of sound/light and other waves as the source and observer move toward or away from each other- waves compress
What is the False Climb Illusion?
Inner ear mistakes acceleration for leaning back
Electromagnetic radiation
Visible light, radio waves, gamma rays, x-rays
Hue
Determined by wavelength
Brightness
determined by amplitude
Saturation
determined by purity
What is Transduction?
Conversion of physical stimuli into changes in the activity of the receptor cells of the sensory organs
What is Psychophysics?
Relationship between physical stimuli and perceptual experience
What are the two kinds of photoreceptors, what are they responsible for, where are they located, and how many are there in the eye?
Rods (120 million): dark and light, light-sensitive
-periphery of the retina
Cones (6 million): wavelengths that are indicative of color
-located in fovea
What is the order of Retinal Circuitry? Which group of photoreceptors are more diffusely connected to bipolar cells?
1st Order: Rod/Cone
2nd Order: Bipolar cells
3rd Order: Ganglion cell
Rods have more bipolar cell connections
What are the two Visual Pathways?
Within Retina: photoreceptor -> bipolar cell -> ganglion cell
Beyond Retina: Ganglion cell -> through optic chiasm -> thalamus -> primary visual cortex (striate)
How is information fed to the occipital cortex?
Via the optic nerve and thalamus
What is the Outer ear made up of?
Channel to tympanic membrane
What is the Middle ear made up of?
Ossicles
Malleus, incus, stapes
What is the inner ear made up of?
Cochlea- Organ of Corti:
Basilar membrane: base
Tectorial membrane: roof
Hair cells in between
Which part of the inner ear distorts according to different frequencies? High frequency vs moderate frequency?
Basilar membrane
High frequency: near base of basilar membrane
Moderate frequency: near apex of basilar membrane
What is tonotopic representation?
Different regions of the basilar membrane project to different areas of the cortex
What can antibiotics do to the inner ear?
Induce hair cell lost first at the base of basilar membrane, which corresponds to loss of high frequency sounds
Which part of the basilar membrane vibrates with the frequency of the sound itself?
The whole tip: apical end
What is Phase difference
Differential push and pull on the eardrums. Sound in in synchrony in front of head, and out of synchrony to the side of head
What is the Sonic Shadow?
Head absorbs high frequencies, excluding the hidden ear
Explain Olfaction
Hair cells in nose extend to epithelium and respond to chemical stimulation
Information goes directly to the olfactory bulb in the cortex, then leaves in olfactory tracts to parts of the brain associated with emotion
What is the sensory organ
Vemeronasal Organ
