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Psychology

<OpenstaxParagraph>
	Scientific knowledge is advanced through a process known as the <OpenstaxTerm>scientific method</OpenstaxTerm>. Basically, ideas (in the form of theories and hypotheses) are tested against the real world (in the form of empirical observations), and those empirical observations lead to more ideas that are tested against the real world, and so on. In this sense, the scientific process is circular. The types of reasoning within the circle are called deductive and inductive. In <OpenstaxTerm>deductive reasoning</OpenstaxTerm>, ideas are tested in the real world; in <OpenstaxTerm>inductive reasoning</OpenstaxTerm>, real-world observations lead to new ideas (<a href="#CNX_Psych_02_01_Reasoning">Figure 2.4</a>). These processes are inseparable, like inhaling and exhaling, but different research approaches place different emphasis on the deductive and inductive aspects.
</OpenstaxParagraph>
<OpenstaxFigure id="CNX_Psych_02_01_Reasoning" src="https://openstax.org/apps/archive/20240226.174525/resources/b330da2563ea2702d5a6bbaab972be7fa518fe54" alt="A diagram has a box at the top labeled “hypothesis or general premise” and a box at the bottom labeled “empirical observations.” On the left, an arrow labeled “inductive reasoning” goes from the bottom to top box. On the right, an arrow labeled “deductive reasoning” goes from the top to the bottom box." mediaType="image/jpeg" width="649" height="351" />
<OpenstaxFigureText width="649">
	Figure 2.4 Psychological research relies on both inductive and deductive reasoning.
</OpenstaxFigureText>
<OpenstaxParagraph>
	In the scientific context, deductive reasoning begins with a generalization—one hypothesis—that is then used to reach logical conclusions about the real world. If the hypothesis is correct, then the logical conclusions reached through deductive reasoning should also be correct. A deductive reasoning argument might go something like this: All living things require energy to survive (this would be your hypothesis). Ducks are living things. Therefore, ducks require energy to survive (logical conclusion). In this example, the hypothesis is correct; therefore, the conclusion is correct as well. Sometimes, however, an incorrect hypothesis may lead to a logical but incorrect conclusion. Consider this argument: all ducks are born with the ability to see. Quackers is a duck. Therefore, Quackers was born with the ability to see. Scientists use deductive reasoning to empirically test their hypotheses. Returning to the example of the ducks, researchers might design a study to test the hypothesis that if all living things require energy to survive, then ducks will be found to require energy to survive.
</OpenstaxParagraph>
<OpenstaxParagraph>
	Deductive reasoning starts with a generalization that is tested against real-world observations; however, inductive reasoning moves in the opposite direction. Inductive reasoning uses empirical observations to construct broad generalizations. Unlike deductive reasoning, conclusions drawn from inductive reasoning may or may not be correct, regardless of the observations on which they are based. For instance, you may notice that your favorite fruits—apples, bananas, and oranges—all grow on trees; therefore, you assume that all fruit must grow on trees. This would be an example of inductive reasoning, and, clearly, the existence of strawberries, blueberries, and kiwi demonstrate that this generalization is not correct despite it being based on a number of direct observations. Scientists use inductive reasoning to formulate theories, which in turn generate hypotheses that are tested with deductive reasoning. In the end, science involves both deductive and inductive processes.
</OpenstaxParagraph>
<OpenstaxParagraph>
	For example, case studies, which you will read about in the next section, are heavily weighted on the side of empirical observations. Thus, case studies are closely associated with inductive processes as researchers gather massive amounts of observations and seek interesting patterns (new ideas) in the data. Experimental research, on the other hand, puts great emphasis on deductive reasoning.
</OpenstaxParagraph>
<OpenstaxParagraph>
	We’ve stated that theories and hypotheses are ideas, but what sort of ideas are they, exactly? A <OpenstaxTerm>theory</OpenstaxTerm> is a well-developed set of ideas that propose an explanation for observed phenomena. Theories are repeatedly checked against the world, but they tend to be too complex to be tested all at once; instead, researchers create hypotheses to test specific aspects of a theory.
</OpenstaxParagraph>
<OpenstaxParagraph>
	A <OpenstaxTerm>hypothesis</OpenstaxTerm> is a testable prediction about how the world will behave if our idea is correct, and it is often worded as an if-then statement (e.g., if I study all night, I will get a passing grade on the test). The hypothesis is extremely important because it bridges the gap between the realm of ideas and the real world. As specific hypotheses are tested, theories are modified and refined to reflect and incorporate the result of these tests <a href="#CNX_Psych_02_01_Method">Figure 2.5</a>.
</OpenstaxParagraph>
<OpenstaxFigure id="CNX_Psych_02_01_Method" src="https://openstax.org/apps/archive/20240226.174525/resources/d961aca4fe0109c144b2cf02d83d988fe8fcd4b6" alt="A diagram has seven labeled boxes with arrows to show the progression in the flow chart. The chart starts at “Theory” and moves to “Generate hypothesis,” “Collect data,” “Analyze data,” and “Summarize data and report findings.” There are two arrows coming from “Summarize data and report findings” to show two options. The first arrow points to “Confirm theory.” The second arrow points to “Modify theory,” which has an arrow that points back to “Generate hypothesis.”" mediaType="image/jpeg" width="975" height="517" />
<OpenstaxFigureText width="975">
	Figure 2.5 The scientific method involves deriving hypotheses from theories and then testing those hypotheses. If the results are consistent with the theory, then the theory is supported. If the results are not consistent, then the theory should be modified and new hypotheses will be generated.
</OpenstaxFigureText>
<OpenstaxParagraph>
	To see how this process works, let’s consider a specific theory and a hypothesis that might be generated from that theory. As you’ll learn in a later chapter, the James-Lange theory of emotion asserts that emotional experience relies on the physiological arousal associated with the emotional state. If you walked out of your home and discovered a very aggressive snake waiting on your doorstep, your heart would begin to race and your stomach churn. According to the James-Lange theory, these physiological changes would result in your feeling of fear. A hypothesis that could be derived from this theory might be that a person who is unaware of the physiological arousal that the sight of the snake elicits will not feel fear.
</OpenstaxParagraph>
<OpenstaxParagraph>
	A scientific hypothesis is also <OpenstaxTerm>falsifiable</OpenstaxTerm>, or capable of being shown to be incorrect. Recall from the introductory chapter that Sigmund <OpenstaxTerm>Freud</OpenstaxTerm> had lots of interesting ideas to explain various human behaviors (<a href="#CNX_Psych_02_01_freud">Figure 2.6</a>). However, a major criticism of Freud’s theories is that many of his ideas are not falsifiable; for example, it is impossible to imagine empirical observations that would disprove the existence of the id, the ego, and the superego—the three elements of personality described in Freud’s theories. Despite this, Freud’s theories are widely taught in introductory psychology texts because of their historical significance for personality psychology and psychotherapy, and these remain the root of all modern forms of therapy.
</OpenstaxParagraph>
<OpenstaxFigure id="CNX_Psych_02_01_freud" src="https://openstax.org/apps/archive/20240226.174525/resources/a5062a5f223bf832ee19dc50ba96cf3b13e9ef36" alt="(a)A photograph shows Freud holding a cigar. (b) The mind’s conscious and unconscious states are illustrated as an iceberg floating in water. Beneath the water’s surface in the “unconscious” area are the id, ego, and superego. The area just below the water’s surface is labeled “preconscious.” The area above the water’s surface is labeled “conscious.”" mediaType="image/jpeg" width="649" height="426" />
<OpenstaxFigureText width="649">
	Figure 2.6 Many of the specifics of (a) Freud's theories, such as (b) his division of the mind into id, ego, and superego, have fallen out of favor in recent decades because they are not falsifiable. In broader strokes, his views set the stage for much of psychological thinking today, such as the unconscious nature of the majority of psychological processes.
</OpenstaxFigureText>
<OpenstaxParagraph>
	In contrast, the James-Lange theory does generate falsifiable hypotheses, such as the one described above. Some individuals who suffer significant injuries to their spinal columns are unable to feel the bodily changes that often accompany emotional experiences. Therefore, we could test the hypothesis by determining how emotional experiences differ between individuals who have the ability to detect these changes in their physiological arousal and those who do not. In fact, this research has been conducted and while the emotional experiences of people deprived of an awareness of their physiological arousal may be less intense, they still experience emotion (Chwalisz, Diener, &amp; Gallagher, 1988).
</OpenstaxParagraph>
<OpenstaxParagraph>
	Scientific research’s dependence on falsifiability allows for great confidence in the information that it produces. Typically, by the time information is accepted by the scientific community, it has been tested repeatedly.
</OpenstaxParagraph>

2.1.3 The Process of Scientific Research

1 Introduction to Psychology

1.1 What Is Psychology?

1.1.1 Why Study Psychology?

1.2 History of Psychology

1.2.1 Wundt and Structuralism

1.2.2 Functionalism

1.2.3 Freud and Psychoanalytic Theory

1.2.4 Wertheimer, Koffka, Köhler, and Gestalt Psychology

1.2.5 Pavlov, Watson, Skinner, and Behaviorism

1.2.6 Maslow, Rogers, and Humanism

1.2.7 The Cognitive Revolution

1.2.8 Multicultural And Cross-Cultural Psychology

1.2.9 Women in Psychology

1.3 Contemporary Psychology

1.3.1 Biopsychology and Evolutionary Psychology

1.3.2 Sensation and Perception

1.3.3 Cognitive Psychology

1.3.4 Developmental Psychology

1.3.5 Personality Psychology

1.3.6 Social Psychology

1.3.7 Industrial-Organizational Psychology

1.3.8 Health Psychology

1.3.9 Sport and Exercise Psychology

1.3.10 Clinical Psychology

1.3.11 Forensic Psychology

1.4 Careers in Psychology

1.4.1 Other Careers in Academic Settings

1.4.2 Career Options Outside of Academic Settings

2 Psychological Research

2.1 Why Is Research Important?

2.1.1 Use of Research Information

2.1.2 NOTABLE RESEARCHERS

2.2 Approaches to Research

2.2.1 Clinical or Case Studies

2.2.2 Naturalistic Observation

2.2.3 Surveys

2.2.4 Archival Research

2.2.5 Longitudinal and Cross-Sectional Research

2.3 Analyzing Findings

2.3.1 Correlational Research

2.3.2 Causality: Conducting Experiments and Using the Data

2.3.3 Reliability and Validity

2.4 Ethics

2.4.1 Research Involving Human Participants

2.4.2 Research Involving Animal Subjects

3 Biopsychology

3.1 Human Genetics

3.1.1 Genetic Variation

3.1.2 Gene-Environment Interactions

3.2 Cells of the Nervous System

3.2.1 Neuron Structure

3.2.2 Neuronal Communication

3.2.3 Neurotransmitters and Drugs

3.3 Parts of the Nervous System

3.3.1 Peripheral Nervous System

3.4 The Brain and Spinal Cord

3.4.1 The Spinal Cord

3.4.2 The Two Hemispheres

3.4.3 Forebrain Structures

3.4.4 Midbrain and Hindbrain Structures

3.4.5 Brain Imaging

3.5 The Endocrine System

3.5.1 Major Glands

4 States of Consciousness

4.1 What Is Consciousness?

4.1.1 Biological Rhythms

4.1.2 Problems With Circadian Rhythms

4.2 Sleep and Why We Sleep

4.2.1 What is Sleep?

4.2.2 Why Do We Sleep?

4.3 Stages of Sleep

4.3.1 NREM Stages of Sleep

4.3.2 REM Sleep

4.4 Sleep Problems and Disorders

4.4.1 Insomnia

4.4.2 Parasomnias

4.4.3 Sleep Apnea

4.4.4 Narcolepsy

4.5 Substance Use and Abuse

4.5.1 Substance Use Disorders

4.5.2 Drug Categories

4.6 Other States of Consciousness

4.6.1 Hypnosis

4.6.2 Meditation

5 Sensation and Perception

5.1 Sensation versus Perception

5.1.1 Sensation

5.1.2 Perception

5.2 Waves and Wavelengths

5.2.1 Amplitude and Wavelength

5.2.2 Light Waves

5.2.3 Sound Waves

5.3 Vision

5.3.1 Anatomy of the Visual System

5.3.2 Color and Depth Perception

5.4 Hearing

5.4.1 Anatomy of the Auditory System

5.4.2 Pitch Perception

5.4.3 Sound Localization

Question	Answer
results are predicted based on a general premise	deductive reasoning
able to be disproven by experimental results	falsifiable
(plural: hypotheses) a testable prediction about how the world will behave if an idea is correct, often worded as an if-then statement	hypothesis
conclusions are drawn from observations	inductive reasoning
well-developed set of ideas that propose an explanation for observed phenomena	theory