Lecture 07 - Helmholtz, Gestalt Psychology & Wundt

Who is Helmholtz and what did he come up with?

1821-1894

Didn’t think of himself as a psychologist but ultimately filled that role and could be seen as a founder of psychology

Expanded on the doctrine of specific nerve energies

Promoted the law of conservation of energy

Established many of the foundations of experimental psychology with his studies of sensation and perception

Non-metaphysical approach to medicine and psychology

What group was Helmholtz a part of?

he was with a group that had an explicit anti-vitalism/anti-metaphysical oath that “no other forces than the common physical-chemical ones are active within the organism”

empirically oriented

no more metaphysical stuff and focus only on physics and chemistry

How did Helmholtz’s conservation of energy demonstrate his approach to psychology?

empirically oriented

• He found that the amount of energy expended by frog muscles generally corresponded with energy intake

What was Helmholtz’s view on physiology?

the body as a machine view showed more pioneering work on nerve conduction speed

mechanistic view

Who was Galvani? What experiment did he do?

first to seriously study electrical activity as an alternative to animal spirits

• He subtracted time between electrical stimulation of a frog's leg and the twitch of the foot, from the time between stimulation of a more distant spot and twitch he could calculate nerve speed

• Used this for human reaction time studies

 

What’s the connection between Helmholtz and Frankenstein by Mary Shelley?

conceptual overlap between these two

Helmholtz didn’t directly inspire her book

book was inspired by Galvani’s research

Frankenstein would have been like Helmholtz’s dream experiment

• nerves and mechanisms coming to life

• and Frankenstein had psychological traits: e.g. lonely with creator left him

What was Helmholtz’s contributions towards vision?

first of all he had better technology for it such as invention of the ophthalmoscope and could now look directly into a living eye and see the retina, fovea, optic disc, blood vessel, etc.

discovered the strengths and weaknesses to the eye as a machine

• e.g. sharpest vision on fovea, blind spot exists, lens limitations

What were Helmholtz’s definitions of sensations and perceptions?

Sensations: the raw elements of conscious experience, which require no learning or prior experience

• E.g. in vision: the spatially organized patches of light with varying hues and brightnesses that fill one's visual field (independent of any meaning)

Perceptions: the meaningful interpretations given to sensations, learned and innate

What was Helmholtz’s trichromatic theory?

he played a key role in understanding colour vision

trichromatic theory: based on various observations about colour mixing, he proposed that the retina does not contain distinct cells responsive to each colour but in fact only cells response to three (red, green, blue)

What was the overall idea behind sensations and how the brain interprets what we see? What is the term unconscious inference?

So what we are seeing is determined as much if not more by our sensory hardware and how that info is out together in the brain

Perceptual adaptations: Helmholtz argued that central NS processing of sensory info didn't stop with just the basic "building blocks"

• Perceptions are influenced by experience as well as innate factors 

• Helmholtz used the term: unconscious inference

Who is Fechner? Who was he inspired by and what did he play a role in?

contemporary to Helmholtz

played a role in continuing development of early psychology

What was Fechner’s view on religion and psychology?

came from a religious background

on one hand he was excited by materialism and empiricism but also conflicted about squeezing the whole soul out of the picture

What was Fechner’s trajectory towards a psychophysics?

he had some sort of existential crisis and went super metaphysical and developed a new age book about plants having souls

then he had an epiphany that math could be used to explain relationships and parts of psychology

• he tried to not just study mental processes experimentally but strove to explain associations in lawful, mathematical terms

• coined the term psychophysics

eventually wrote a book called “Elements of Psychophysics” that popularized this perspective

What is the just noticeable difference and who did Fechner collaborate with?

worked with Ernst Weber and created a sensory measure of the just noticeable difference (jnd)

jnd = the minimum amount of difference between two stimulus intensities necessary for an observer to tell them apart

What is Fechner’s law?

the observed relationship between physical and subjective stimulus intensities for many different senses can be expressed by S = k log P

• really more like Fechner’s rule of thumb since the overall concept is right that its its easier to detect things with low background stimulation

What were the conceptual similarities with Kant, Helmholtz and Gestalt psychology?

the brain organizes and puts its own spin on perceptions and experiences

• making the sum greater than its parts

What did Gestalt psychology emphasize?

emphasized how the mind imposes its own order on perceptual info

• early Gestalt psychologists were with Team Kant (vs. Team Helmholtz) in that they believed this was an innate process

  • aka you can’t avoid phi phenomenon

What is true about differences in how people organize perceptual info? What is Rorschach test?

people sometimes differ in the order they organize ambiguous stimuli

Rorschach test: ambiguous stimuli → individual reactions may reveal aspects of personality

Who was Wilhelm Wundt?

1832-1920

German psychology who established the first psychology lab

contributed in the infrastructure side of psychology

Was Helmholtz's assistant for many years

Lucky to be at the right place and time in scientific culture and promoted psychology and himself a lot

• Good reviews (e.g. from William James)

What were Wundt’s experiments related to?

involved mental chronometry - measurements of time intervals between different events (to get a sense of mental processing time)

• built on his work with Helmholtz

reasoned that if peripheral nerve conduction takes time then maybe mental events themselves (mediated by the neurons in the brain) take time and things like sensations, attention and decision making would be reflected

What was Wundt’s thought meter?

Bar attached to a clock pendulum would occasionally ring the bell

Participant asked to focus on bottom of pendulum

When you hear the bell, tell me where the pendulum was

Where they identified the pendulum was always a little further along that actual

Reflected processing time in the brain

The fact that perception was not instantaneous reinforced the idea that mental processes = mechanistic processes

What were Wundt’s subtractive method studies’ premise?

Simple reaction time was measured by presenting a stimulus (e.g. number) and having participant respond ASAP (raw reaction time to neutral stimulus)

Then presented other stimuli that required some kind of thinking (e.g. two numbers and you have to determine which is larger)

Subtracting the first time allowed for estimation of the decision process

lots of variation involving different mental processes (different colours, letters)

Who were Wundt’s influential students?

James McKeen Cattell, G. Stanley Hall, Edward Titchener, Lightner Witmer

What was Wundt’s term apperception and who did he continue this idea from?

He continued with Leibniz's term apperception: the process that occurs when stimuli or ideas are 'registered' in consciousness

Besides his experiments on reaction time, what did Wundt study? What were some challenges with introspection?

Wundt was known for his experiments on reaction time however he did study introspection as well

• Results were less predictable since they involve free will and psychic causality rather than purely mechanical causes

Wundt didn't think that all psychological processes could be tested experimentally: higher processes like language and memory needed less quantitative approaches liked controlled introspection

What is Volkerpsychologie?

Wundt's non-experimental branch of psychology dealing with the communal and cultural products of human nature, such as religions, mythologies, customs, and languages. Sort of blend of archeology, sociology, history, etc.

What was Wundt seen as in the field of psychology?

by 1874, Wundt wrote the book considered to be the “founding” textbook for psychology

Wundt was recognized as the founder of psychology