Sensation _ Perception - lecture 5 - structure and functions of the eye

Sensation _ Perception - lecture 5 - structure and functions of the eye

Info iconThis preview shows pages 1–18. Sign up to view the full content.

View Full Document Right Arrow Icon
Structure and Functions of the Eye Lecture 5
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Neuron
Background image of page 2
The Neuron Types of Neurons Sensory neuron  communicates info about external world to other neurons. Interneuron  communicates info between neurons. Motor neuron  sends nerve impulses from CNS to muscles.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Neuron Neuronal Communication Resting Potential  typically about -70 mV. Action Potential  abrupt change in neuron’s charge … AKA neural spike.
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Visual System Humans dominant, and possibly most important, sensory system. “The eyes are the window to the soul.” Processes distal objects via bottom-up processing through the medium of light… occurs outside of awareness.
Background image of page 6
The Visual System What is the most basic property of vision? Requires and depends on the presence of light. Can often sense light before filling in the details (shape, form, etc).
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Visual System Light does not simply enter the CNS and produce a photographic image … Enters eye and is transformed. Process is known as sensory transduction . Sensory organs serve as transducers. Funneling Effect.
Background image of page 8
Visual Stimulus What is light? Light = a kind of electromagnetic radiation. Electromagnetic radiation = all forms of waves produced by electrically charged particles.
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Visual Stimulus Light humans can see represents only a small portion of the electromagnetic radiation spectrum. Approximately 400 nanometers (violet) to 700 nanometers (red). Variation between species in response to portions of the electromagnetic spectrum.
Background image of page 10
The Visual Stimulus Light is also made up of waves and we can describe light in terms of wavelengths. Wavelength = the distance light travels during one cycle; the distance between two peaks.
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Visual Stimulus Wavelengths are typically measured in nanometers (nm). Nanometer = 1 billionth of a meter. Light = the portion of the electromagnetic spectrum made up of waves from about 400 nm to 700 nm.
Background image of page 12
The Visual Stimulus Properties of light: Wavelength Purity Amplitude Purity = the mixture of wavelengths in the light. Amplitude = the height of the light wave.
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Visual Stimulus Physical Properties Wavelength Purity Amplitude Psychological Properties Hue Saturation Brightness
Background image of page 14
The Eye
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Eye Sclera = white external membrane. Cornea = clear membrane, joined to sclera. Slightly bulges out. Simple fixed lens that begins the process of gathering light and concentrating it. About 66% of the bending of incoming light is done by the cornea. Astigmatism Result of misshapen cornea … incoming light is blurry.
Background image of page 16
The Eye Location of cornea (at the front of the eye) can result in other problems.
Background image of page 17

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 18
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 68

Sensation _ Perception - lecture 5 - structure and functions of the eye

This preview shows document pages 1 - 18. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online