Ch.5

The process of transduction

Transduction is a process by which sensory receptors produce neural impulse s when they receive physical or chemical stimulation. Receptors specialized neurons in the sense organs, pass impulses to connecting neurons when the receptors receive physical or chemical stimulation. Connecting neurons then transmit information to the brain in the form of neural impulses.

The concept of difference threshold

Difference threshold is the just noticeable difference between two stimuli- the minimum amount of change required for a person to detect a difference. Difference threshold increases as the stimulus becomes more intense. Weber’s law states that the just noticeable difference between two stimuli is based on a proportion of the original stimulus rather than on a fixed amount of difference.

The receptors for sound and how they are activated

Changes in air pressure produce sound waves that arrive at the outer ear and travel down the auditory canal to the eardrum, a membrane stretched tightly across the canal and marking the beginning of the middle ear. The sound waves make the eardrum vibrate. Vibrations are transferred to ossicles, three tine bones. The ossicles transfer the eardrum’s vibrations to the oval window, a membrane of the cochlea, the cochlea is the thins basilar membrane. The oval window’s vibrations create pressure waves in the inner ear’s fluid; these waves prompt the hair cells to bend and cause neurons on the basilar membrane to fire.

The three psychological dimensions of color

The psychological dimensions of color are through the addictive and subtractive color. The evidence of this is through the rods and cones in our occipital lobe of our brain. These different colors are all linked.

The concept of opposite colors

Opposite colors are involved in the McCollough effect. Celeste McCollough was named for the vision research. A type of ganglion cell may receive excitatory input form L cones. These create the perception that red and green are “opposite”.

What are hits and false alarms, and how are they used in signal detection theory to spate the experiment participant’s sensitity to a signal from the response bias of that participant?

If the signal is presented and the observer detects it, the outcome is known as a hit. If the participant fails to detect the signal, the outcome is a miss. If the participant “detects” a signal that was not presented, the outcome is a false alarm. Response bias refers to a participant’s tendency to report detecting the signal in an unclear trial. The participant might be strongly biased against responding and need a great deal of evidence that the signal is present. Under other conditions, that same participant might need only a small amount of evidence.

Where is light transformed into neural signals and how do these neural signals reach the primary visual cortex?

Light is transformed into neural signals in our occipital cortex. These neural signals reach the primary visual cortex through the rods and cones. Rods are retinal cells that respond to low levels of illumination and result in black and white perception. The cones are retinal cells that respond to higher levels of illumination and result in color perception.

What evidence indicates that our ability to see colors is based upon three underlying components?

The evidence that indicates our ability to see colors is through subtractive color mixing and addictive color mixing. In subtractive color mixing when the colors red, yellow, and blue are mixed together, in the middle of those three colors when a light is shined on that spot it shows black, which shows that the mixing pigments are black. In addictive color mixing when those same three colors are mixed and a light shined on them the color shown is white, which means that the mixing color is white.

What evidence indicates that our ability to perceive the identity of an abject is somewhat separate from our perception of the location? What areas of the brain are involved in these perceptions?

Addictive coloring mixing is a way to produce a given spectral pattern in which different wavelengths of lights are mixed. The precept is determined by the interaction of these wavelengths with receptors in the eye and is a psychological process. Addictive is a mixing of light (white). Subtractive color mixing is a way to produce a given spectral pattern in which the mixture occurs within the stimulus itself and is actually a physical, not psychological, process. Subtractive color mixing is the mixing of pigments (black).

How are we able to perceive objects or even pictures, as three-dimensional that is, as having depth?

We are able to perceive objects because of our depth perception through binocular cues, and monocular cues. Binocular disparity which is our views are different up close to our eyes. Our binocular disparity gets goes down as objects get farther away, and when the greater disparity the closer the object is. The other part of depth perception is monocular cues. In monocular cues you see an object with just one eye. An example is familiar size, we know how large familiar objects , so we can tell how far away they are by the size of their retinal images.