Scenario B Fact Check: A Case Study

As we age or incur visual impairment, we may need brighter light when reading. Explain why this is the case.

 A.accommodation B.the concentration of cones in the fovea C.chemical structure of the vitreous humor D.the prevalence of amacrine cells in the

The retina is what houses the eye’s rods and cones. The eye has about 6 million cones and 120 million rods. Both rods and cones get their names from their shape. Rods do not provide color vision, and are sensitive to dim light. Cones function well in the day and provide color vision.

To understand the diverse causes of RP, a basic understanding of visual perception is required. Phototransduction (conversion of light to electrical signals) occurs first, which is initiated by two types of photoreceptors: rods and cones. These two types vary in their function as rods are primarily responsible for night vision and lack sensitivity to color while cones function in color vision. Light contacts these photoreceptors, and isomerizes a retinaldehydechromophore (retinal) which is bound to varying types of opsin proteins corresponding in their reactivity to different wavelengths of light. Upon absorption of a photon of light, the chromophore 11-cis-retinal is isomerized to the all-trans confirmation, which subsequently causes a series of molecular interactions which ultimately result in the electrical response of the photoreceptors (Vugler 2010). As 11-cis-retinal is required to absorb photons of light, this compound must be regenerated, a function that is performed with the aid of nearby cells of the retinal pigment epithelium

Fig. __ Feed-forward projections from the eyes to the brain and topographic mapping. In each eye the visual field on the left and right of the fovea (the cut goes right through the fovea!) projects to different cortical hemispheres: the ipsilateral retina projects to the ipsilateral visual cortex, and the contralateral retina crosses the contralateral cortex (hemifield crossing in the optic chiasma). The first synapse of the retinal ganglion cells is in the lateral geniculate nucleus (LGN), but information from the left (L) and right (R) eye remains strictly separated. The LGN consists of six layers, layers 1 and 2 are primarily occupied by the magnocellular pathway, and 3–6 by the parvocellular. Information from both eyes comes first together

According to current research there are about 800,000 ganglion cells in the human optic nerve (J.R. Anderson, 2009,pg. 35). The ganglion cells are where the first encoding of the visual information happens. Encoding is the process of recognizing the information and changing it into something one’s brains can understand and store. Each ganglion cell is dedicated to encoding information from a specific part of the retina. The optic nerve goes then to the visual cortex and the information enters the brain cells. There are two types of cells that are subcortical, or below the cortex; the lateral geniculate nucleus and the superior colliculus. The lateral geniculate nucleus is responsible for understanding details and recognizing objects. The superior colliculus is responsible for understanding where objects are located spatially. This collection of cells working together is called the “what-where” distinction. The division of labor continues, as the information is further processes. The “what” information travels to the temporal cortex, the “where” information travels to the parietal regions of the brain.

The eyeball holds many parts to allow eyesight. The retina holds the key to allowing the human eye to see color. The pupil appears as the black part of the eye that people see, the pupil however does not have much to do with comprehending color. As Clarence Rainwater said in his book “The pupil is simply the hole in the iris through which light enters the eye.” (84) The light then has to pass through many parts of the eye before reaching the retina such as the transparent cornea, the aqueous humor, the lens, and the vitreous humor. Clarence Rainwater described the retina as “... the eye’s sensitive inner surface.” (86) The exciting part of the eye starts here. The retina holds the key as stated by Clarence Rainwater, “... a complex system

The eye is made up of many components, including the cornea, pupil, iris, and retina, along with others. Within the retina are rods, cones, and a fovea. Rods are responsible for the black, white, and gray colors we see, along with our peripheral vision. Our cones help us see detail, along with allowing us to see colors, specifically red, green, and

We will use a match-to sample paradigm to test color vision. In the match-to sample paradigm, animals are presented with a

Humans have three cone cells that are extremely sensitive to Red, (620-700nm), Green (490-570nm) and Blue (450-495nm) wavelengths of light. Although these three cones are most sensitive to these wavelengths, they are still sensitive to the remaining wavelengths of visible light between 400-700nm. When a light with a wavelength of 600nm is transmitted through the retina, the Red and Green cones capture, sense and signal the brain that orange light is observed. In this case the Red and Green cones absorb light but the Green cones are less sensitive. Also, the Blue cones don’t absorb much light and are not sensitive

When analyzing Scenario B there are 3 major statements that are inconsistent with the textbook and lectures. The first statement being, “dogs respond best to classical conditioning as they need consequences to understand how we expect them to behave.” (Scenario B, 2014) However, according to Lilienfeld et al. (2014) the definition for classical conditioning on p. 212 is the, “form of learning in which animals come to respond to a previously neutral stimulus that has been paired with another stimulus that elicits an automatic response,” and the definition of operate conditioning on p.220 states, “learning controlled by the consequence of the organism’s behavior.” Provided this the term classical conditioning

In his first White House Press Briefing, Press Secretary Sean Spicer asserted that President Donald Trump’s inaugural crowd was the largest in history. This claim was quickly proven to be false by various media outlets. Following his statements, Senior Adviser Kellyanne Conway clarified his assertions as being “alternative facts.” The use of the phrase has resulted in an accentuated social divide and an onset of political protest.

A debated topic that I did not include in my analysis included avian visual models. Birds have been shown to see in ultraviolet light (300-400nm), which humans are blind to (Cuthill et al. 2000). Birds have four cone types, while humans only have three, and so likely see the intensity of colours differently (Chen & Goldsmith, 1986; Goldsmith, 1991). They also have light-absorbing oil droplets in their cone cells, which is likely to reduce the overlap between cone sensitivities (Bowmaker et al. 1997; Vorobyev, 2003). From this, studies have found that there are two types of colour vision in birds, VS and UVS. Both vision models see in ultraviolet light, however UVS sees more towards the shorter wavelengths while VS sees towards the longer

The fact checks have provided a unique opportunity to think critically about what candidates say and to check if they are telling the truth. The fact checks also made me aware of what claims can actually be checked and the important things to look for when checking a claim. Even if I do not write another fact check in my life, I can still go through the process in my head whenever I hear a claim, and that is more than most people can do.