Hypothesis And Variables: Researchers Wonder How We

Hypothesis And Variablesscenariosa Researcher Wonders How Well The Se

Hypothesis and Variables Scenarios: A researcher wonders how well the sense of smell functions during sleep. In general, we know that our sensory systems operate at a higher threshold during sleep. That is, a more intense stimulus is required to elicit a response during sleep than during wakefulness. Furthermore, we are less responsive during some stages of sleep than during others. Experiments using sounds suggest that we are less responsive during stages 3 and 4 sleep (deep sleep) than during stages 1, 2, or REM sleep (lighter sleep).

Thus, the researcher predicts that research participants will be less responsive to odors during stages 3 and 4 sleep than during the other stages of sleep. The researcher devises a system for delivering odors while college students sleep in the laboratory. Peppermint fragrance is delivered at specific times through a modified oxygen mask that the students wear while they sleep. Electrodes are attached to each student’s scalp, face, and chin to determine sleep staging. Electrodes are also attached to each student’s chest to record heart rate.

A change in heart rate following presentation of the odor is used to indicate that the participant detected the odor. Instructions: Read the scenario above and answer the following questions: What is the research hypothesis? What is the independent variable? Is the independent variable a qualitative variable or a quantitative variable? Explain.

Paper For Above instruction

The primary research hypothesis in this scenario posits that participants will exhibit decreased responsiveness to odors during deep sleep stages, specifically stages 3 and 4, compared to lighter sleep stages such as stages 1, 2, or REM sleep. More formally, the hypothesis could be articulated as: "Participants' sensitivity to olfactory stimuli, as measured by heart rate changes, is lower during stages 3 and 4 sleep than during stages 1, 2, and REM sleep."

The independent variable in the study is the stage of sleep, which encompasses stages 1, 2, 3, 4, and REM sleep. This variable influences the participant's responsiveness to odors, which is the dependent variable. The sleep stages are determined through EEG recordings from electrodes attached to the scalp, face, and chin, allowing the researchers to classify each period of sleep accurately.

Regarding the nature of the independent variable, sleep stage is a qualitative (categorical) variable. It comprises discrete categories or groups—namely, the different sleep stages—without inherent numerical values. Each participant's sleep state at the time of odor delivery falls within one of these categories, and responses are analyzed based on these categorical distinctions.

The researchers might wish to use multiple dependent variables to obtain a comprehensive understanding of the effects of sleep stages on sensory responsiveness. For instance, in addition to heart rate changes, they could also measure neural responses (via EEG), self-reported awareness (if feasible upon awakening), or other physiological responses like skin conductance. Utilizing multiple dependent variables offers a multi-faceted perspective on sensory processing, increasing the robustness and validity of the findings by cross-verifying results across different measures.

A notable limitation of this study is the artificial environment of the sleep laboratory, which may influence natural sleep patterns and responsiveness. Participants might sleep differently in a laboratory setting compared to their usual environment, introducing a form of ecological validity concern. Additionally, the use of a single odor (peppermint) limits the generalizability of the findings to other types of odors or sensory stimuli. Furthermore, opioid responses might vary individually, and heart rate as an indicator may not fully capture odor detection sensitivity, potentially leading to false negatives or positives in response attribution.

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