1. history

Psychology as a Science

• Psychology today is considered a science because it consists of hypotheses that are falsifiable through evidence.
• Two hundred years ago, psychology was not considered a science.
• Psychology is the scientific study of the mind and behavior.
• Early accounts focused on establishing facts rather than testing theories using inductivism.
• Descartes proposed the separation of mind and body to free science from religion diplomatically.
  • The Church had jurisdiction over the mind.
  • Science explored the body.
  • Psychology, as a study of the mind, was excluded from science.
• The word ‘psychology’ translates from Greek as ‘the study of the soul,’ leading to associations with spiritual and paranormal phenomena.
• Psychology began to be considered a science only when it disassociated from paranormal phenomena.

Very Early Beginnings

• Science is cumulative; research builds on previous research.
• The first psychology laboratory, ‘new psychology,’ was established by Wilhelm Wundt in 1879.
• Wundt's work was influenced by earlier research.
• New psychology integrated:
  • Study of sensation: sensory physiology provided a scientific approach to studying sensation.
  • Associationist philosophy: contributions from the philosophy of mind showed that higher mental processes could be studied.
  • Neuroscience: medical findings linked higher or cognitive processes to the brain.

Sensory Physiology, Sensory Psychophysiology, and Psychophysics

• Ernst Weber studied how sensory nerve stimulation gives rise to sensations.
• Weber aimed to measure sensations and called this field sensory physiology.
• Just Noticeable Difference (JND): The smallest difference between two stimuli that leads to a person pointing out that they are different.
• Weber's Law: there was a relationship between a JND between two stimuli and the magnitude of the stimuli.
• Weber's Law: The ratio of the JND to the stimulus intensity is approximately constant: \frac{JND}{Stimulus \ intensity} = Constant
• Gustav Theodor Fechner, a student of Weber, built on his research.
• Weber named the field ‘sensory psychophysiology,’ but Fechner called it ‘psychophysics’.
• Fechner developed two methods of assessing thresholds:
  • Method 1: Participants compare pairs of objects and determine if they are different.
    • Advantage: Avoids the problem of differing criteria for difference.
  • Method 2: Participants adjust a stimulus to match another.
    • The method of average error or method of adjustment is used, taking the average of errors as a measure of JND.

Fechner’s Law

• Fechner showed that Weber’s law followed a logarithmic function: S = k \cdot log(I), where S is the psychological sensation, k is a constant, and I is the physical stimulus intensity.
• Weber and Fechner’s laws make quantitative predictions about JND increase.
• Fechner developed experimental aesthetics, hypothesizing that rectangles with a ratio of 1 to 1.62 (golden ratio) are more aesthetically pleasing.
• Later research found Fechner’s results anomalous.

British Associationist Philosophy

• Tabula rasa: John Locke’s idea that the mind is blank at birth and filled with experiences.
• David Hartley suggested the brain and nervous system were connected to thought.
• Hartley believed the brain, spinal cord, and nerves contained vibrating particles; moderate vibrations caused pleasure, and large vibrations caused pain.
• James Mill suggested ideas enter the mind and become fixed.
• John Stuart Mill initially agreed but later diverged after observing chemical combinations.

Brick Wall Hypothesis & Coalescence Theory

• Brick wall hypothesis suggests limits to mental associations.
• Coalescence hypothesis suggests complex mental representations emerge from simpler associations.

Findings from Neuroscience – Localization of Function

• Physicians compared brains of people who died of disease and natural causes.
• Pierre Broca discovered Broca’s area (frontal lobe) associated with speech production.
• Carl Wernicke discovered Wernicke’s area (left temporal lobe) associated with connecting speech with meaning.
• Damage to Broca’s area leads to slow, halting speech.
• Damage to Wernicke’s area impairs language comprehension.
• Localization of function: different brain parts have different functions.

The Case of Phineas Gage

• Phineas Gage’s prefrontal cortex injury altered his personality.
• Damage led to irritability and poor decision-making.

Hermann Ludwig von Helmholtz

• Helmholtz studied sensory psychophysiology and measured the speed of nerve impulse conduction.
• He contributed to vision theory and developed optical instruments.

Wilhelm Wundt

• Wundt developed a link between physiology and sensory perception.
• Wundt demonstrated that the experimental method used in the study of physiology could be applied to psychology.
• He combined his knowledge of medicine, physiology, and philosophy.
• He established that the paranormal was not included in the field of new psychology.
• Independent and dependent variables appeared in the 1930s, along with the idea of control conditions in medicine.
• Wundt emphasized that psychology should focus on fundamental science (research aimed at understanding fundamental problems) and is not an applied science (application of fundamental scientific knowledge to solve practical problems).

Wundt believed that there should be two types of psychology:

• Experimental psychology: Uses scientific methods with active manipulation of variables.
  • The experimenter actively manipulates a variable and observes the result.
  • Wundt insisted that the paranormal falls outside this type of psychology.
• Völkerpsychologie or folk psychology: Studies culture, rituals, religion, etc., without scientific methods.
  • Here, the psychologist observes what happens and reflects.
• Experimental and observational studies: Experimental involves variable manipulation; observational involves observing without manipulation.

Wundt’s Experimental Psychology

• Wundt focused on immediate experience (direct reaction independent of prior knowledge) rather than mediate experience (reaction mediated by knowledge).
• Wundt’s introspection, or ‘inner perception,’ focused on the sensation itself, not its interpretation.
• Inner perception required training due to the natural tendency to report mediate experience.

Rules for Inner Perception

• The observer needs to be properly trained.
• The observer should know when the stimulus is about to be presented.
• The observer must be in a state of strained attention.
• The stimulus must be repeated several times.
• The stimulus must be varied, and the effect on immediate experience must be noted.

Wundt’s Principle of Psycho-Physical Parallelism

• Mind and body exist and are active simultaneously but do not directly interact (no causal relationship).
• Each follows its own path of development: psychic causality (mind) and physical causality (body).
• Wundt’s interpretation aligns with methodological complementarity: reality is fully described by incompatible descriptions.
• The underlying reality is physical, but a psychological description is necessary.

Goals of Psychology (Wundt)

• Analyze the contents of consciousness into basic elements.
• Discover how these elements are connected.
• Determine the laws underlying the connections between elements.
• Wundt based these goals on achievements in chemistry, aiming for a psychological equivalent of the periodic table.

The Elements of Consciousness: Sensations and Feelings

• Two elements of consciousness: sensations and feelings.
  • Sensations: Connected to a particular sensory modality, referring to an event in the environment.
  • Feelings: Not associated with a sensory modality or linked to an event.
• Wundt’s three-dimensional theory of feeling:
  • Pleasurable/Unpleasurable
  • Exciting/Depressing
  • Relaxing/Straining

Association and Apperception

• Contents of the mind are associated in two ways: associations (passive) and apperceptions (active).
• Apperception involves intention and effort to find connections, requiring attention.
• Emphasis on attention led Wundt to describe this system as voluntarism.
• Voluntarism meant immediate experience reflected inattention.
• Relevance to cognitive behavior therapy and mindfulness meditation.
• Wundt suggested creative synthesis occurs when elements of consciousness are associated or perceived.

Gestalt Movement

• Emphasizes that human perception organizes sensory information into meaningful groups.
• Introduced ideas: seeing the whole as greater than its parts, filling in missing information, and grouping objects based on proximity, similarity, and continuity.

Völkerpsychologie

• Wundt believed higher mental processes couldn't be studied experimentally.
• Demonstrated in his work