Paragraph Coherence: Linking excerpt from, "The Importance of a Well-Groomed Child"
Robert M. Sapolsky
Science 277 (12 September 1997): 1620More than 40 years ago, Seymour Levine and his colleagues uncovered the effects of "neonatal handling" (2). Human handling of newborn rats for 15 min daily during the first few weeks of life produced salutary neuro-encocrine, neurochemical, and behavioral changes in the adult. However, rats handled at later points in time did not produce the same changes (3). One of the most interesting changes was the decreased secretion of glucocorticoids. These hormones are released by the adrenals during stress, and glucocortocoid excess can have numerous deleterious effects. These include damage to the nervous system, where chronic glucocortocold excess can accelerate the loss of certain classes of neurons during aging. And indeed, handled rats do have less neurodegeneration and fewer cognitive deficits in old age (4).
Some mechanisms underlying the handling effect on glucocorticoid secretions have been uncovered (3). Handling triggers thyroid hormone release, which appears to activate ascending serotonegic projections into the hippocampal region of the brain. Serotinin can cause long-lasting increases in glucocorticoid receptor number in hippocampal neurons. The hippocamus helps to mediate negative feedback inhibition of subsequent glucocorticoid secretion, and the higher receptor density enhances the sensitivity with which the hippocamus detects circulating glucocortocioid levels, resulting in more tightly regulated feedback inhibition.
Application
Read each paragraph carefully considering the following:
a) How can I/ the author make the topic sentence more argumentative?
c) Give 1-2 specific suggestions as to how the author can use the LINKING strategy to tighten this paragraph. If you are working on your own paper, revise accordingly.
c) Using the LINKING strategy, determine which sentences do NOT belong in the paragraph.