Movement, Cycles and Rhythms

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Please answer a total of 3 questions for this assignment. Select a question to answer for each of the sections below (Movement, Cycles and Rhythm, Visual System and Auditory System).1.Movement, Cycles and RhythmsThe control of movement is often divided into mechanisms of reflexes and of voluntary movement.What is a reflex? It is a stereotyped, automatic movement evoked by a specific stimulus. It is uniform across members of a species. Some examples in humans are the patellar or kneejerk reflex, the salivary reflex, the orienting reflex, and the pupillary reflex.In reviewing the reflex arc, pay special attention to proprioception, muscle spindles, the stretch reflex, and primary motor cortex. (Prof. Suzuki also discusses the basal ganglia and the cerebellum, but in another lecture that I have not assigned.)Further, let’s think about the cycles in our behavior. They are ancient and varied. We certainly inherited them from species that evolved earlier than we did.We harbor a number of rhythms. Generally, we have cellular cycles that augment the day-night rhythm to regulate our behavioral cycles. There are possibly very long cycles that govern our evolution. Men and women both run on cycles, though with differences. But do our cycles still make biological sense?Questions (answer one only)1) Can you point to any movements that do not involve reflexes–or some reflexes that do not involve movement?2) Sleep is tied to recovery of normal function and memory formation. Why does it make sense, then, to stop for sleep just because the sun sets? Why not sleep just whenever we have a backlog of memories to form or we’re under stress or sick? Does the wide variation in our daily experience require such an extreme regularity of sleep regulation? Since we don’t learn or exercise the same amount each day, why do we nevertheless sleep the same amount? A number of possible answers are given in the first 10 minutes of this fascinating podcast but offer your own insights as well.3) Furthermore, women show more pronounced cycles in sex hormones than men do, including menstrual cycles and a rather imprecise biological clock with a different origin. Is this an evolutionary leftover, no longer necessary or helpful for humans? Would you want the equivalent of a birth control pill for all of our cycles?2.Visual SystemIt’s easy to get swamped in detail about the visual system. (This animation may help.)Videos 10 and 11 discuss the visual pathways that originate in the retina and “ascend” to the visual cortex via the thalamus.In this week’s resources the retina is revealed as more than a screen for images. Light falls on different classes of photoreceptors, rods and cones, which organize light stimulation according to their pigments by intensity and wavelength. From the duplex nature of the retina there arises a tradeoff between greater acuity in the center and greater sensitivity in the periphery. The output of the retina is further organized into receptive fields, and sideways connections between the photoreceptors and horizontal cells sustain lateral inhibition that sharpens contrasts. A retinotopic map is preserved by the visual pathways all the way to the visual cortex; on the other hand, the image still requires a lot of interpretation by the brain.Yet when we look at the world we notice only the rich panorama of detail that relayed to the brain via the fovea.Questions (answer one only)1) How is the retina different from a movie projection screen? Try to be specific.2) How on earth did we end up with eyes that are mostly peripheral retina andonly tiny foveas? Should a sensible retina have more foveas—or larger ones, perhaps? Or might peripheral retina be more than leftover real estate?3.Auditory SystemChoose one part of the human ear (or ears in other animals or the auditory pathways) and describe its contribution to hearing.Try not to duplicate what another class member has chosen. You have many choices:pinnaear canaleardrum (tympanic membrane)ossicles (malleus, incus, stapes)middle ear muscles (tensor tympani, stapedius)oval windowround windowbasilar membranetectorial membraneauditory nerveEustachian tubeinner hair cellsouter hair cellsdifferences in animal ears (whales, birds, bats, desert animals)earwax (cerumen)Hensen’s stripe (obscure)cochlear nucleiinferior colliculimedial geniculate nucleusprimary auditory cortex

Impact of media and public perceptions

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On May 18, 1927, a farmer angered by property taxes that helped build a local school building in Bath, Michigan, murdered his wife, burned down his house, detonated over 1,000 pounds of dynamite he had placed within the school, then drove his truck up to the school and discharged another explosive killing 45 people, most of whom were children, and injuring another 58. On April 20, 1999 (72 years later), two students at Columbine High School in Littleton, Colorado, carried out a highly planned massacre involving multiple explosives and a shooting spree ending in the deaths of 14 people (including the perpetrators) and the injury of 21 more.The Bath, Michigan, disaster drew limited media coverage lasting roughly a week and the story all but vanished from headlines. The Columbine shooting, however, remains a turning point in the perception of safety in schools. One major reason for this is the explosion of news coverage and the intense, long-lasting analyses of this and other acts of mass school violence.Post by Day 3 a response to the following:·  How does the media shape society’s viewpoint of mass violence?o  What are the similarities and differences between the two school disasters with regard to the mindset of the attackers?o  Are school children safer now than they were then? Explain your answer.o  Is media overstating school violence or creating copycat events? Why, or why not?·  Does media contribute to stereotypes of crime? Explain your rationale.·  How has the explosion of social media and 24-hour news coverage impacted our perceptions of violence vs. the impact of more traditional radio and television news coverage? Provide an example.

PTSD

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Find an article about methods used to diagnose PTSD that talks about =4-5 references for your topic. The reference list needs to be in APA format. Thank you.methods used to diagnose PTSD – comparative methods approach, looking at the literature in rates of diagnoses with the PCL, CAPS, etc.Introduction to the topic that you picked:  Overview of the specific type of traumaReview of the research literature- discuss the methods of the papers, the participants, the hypotheses and were they confirmed or disconfirmedWhat are the limitations of the papers reviewed in terms of the methodologyOverall research to date- conclusions and recommendations for future studies