Psychology 205Perception

Tues, 21 Jan 03Day 01

Course Website: http://courseinfo.cit.cornell.edu/courses/psych205

OutlineMetaphysics, ontology, cosmology (ontogeny), & epistemology“Qualities” of Boyle and Locke primary - extension, shape, motion/rest, number, solidity secondary - color, taste, sound, warmth, smellDescartes & dualismDoctrine of the Specific Energy of Nerves, or: Doctrine of Sensory Qualities -- Johannes MüllerConjecture of Dubois-ReymondMolyneux’s paradox

Metaphysics

meta ta physika = “after the things of nature”

Aristotle (384-322 BCE)

Metaphysics

OntologyCosmologyEpistemology

Metaphysics

Ontology: What is there?Cosmology: Where did it come from?

(in biological development: Ontogeny)Epistemology: How do we know it?

MetaphysicsEpistemology: How do we know it?

2 options:knowledge comes to us innately, “innate ideas”

MetaphysicsEpistemology: How do we know it?

2 options:knowledge comes to us innately, “innate ideas”knowledge comes to us through our senses, we know because (of what) we

perceive

“Qualities” of Boyle and Locke (17th cent)and elaborated from Aristotle

“Qualities” of Boyle and Locke

primary - extension, shape, motion/rest, number, solidity

“Qualities” of Boyle and Locke

primary - extension, shape, motion/rest, number, solidity

secondary - color, tonality, warmth, taste, smell

the five senses, five epistemic channelsAristotle, De Anima

Latinate Anglo-Saxon

vision to see seeing, sight audition to hear hearing cutaneousto touch touching, feeling sensegustation to taste tasting olfaction to smell smelling

La dame à la licorne

1483-1500 Flemish, now in the Musée

de Cluny, Paris,details

vision

audition

touch

taste

smell

Jan Brueghel de Velours & Pierre Paul Rubens, Allegory of the senses, 1617-1618, Prado, Madriddetails

vision

audition

touch

taste

smell

Hans Makart, The five senses, ~1880, Osterreichische Galerie, Vienna, details

vision

audition touch taste olfaction

Other modalities:

kinesthesishaptics = touch + kinesthesis

vestibular & spatial orientationbody schema

pain

available on website

available on website

Extra credits

3 max

http://node15.psych.cornell.edu/susan/extracredit

Descartes (17th cent) & dualism

mind -> mentalbody -> physical

Descartes & dualism

mind -> mentalbody -> physical

brain -> physical

dualism

mind & brain

dualism

mind & brain

philosophy biologycognitive science neurophysiology

dualism

mind & brain

philosophy biology

perceptual neurons & neural phenomena circuitry

dualism

mind & brain

philosophy biology

perceptual neurons & neural phenomena circuitry

“red”

The Doctrine of the Specific Energies of Nerves

AKA: Doctrine of Sensory Qualitiesan explanation of the

secondary qualities of Locke & Boyle

Johannes Müller (1838) Handbuch der Physiologie des Menschen, Vol.

V, (English translation by William Baly,

1842).

also available on website

I. External agencies can give rise to no kind of sensation which cannot also be produced by internal causes, exciting changes in the condition of our nerves.

II. The same internal cause excites in the different senses different sensations, in each sense the sensations peculiar to it.

III. The same external cause also gives rise to different sensations in each sense, according to the special endowments of its nerve.

IV. The peculiar sensations of each nerve of sense can be excited by several distinct causes internal and external.

V. Sensation consists in the sensorium's receiving through the medium of the nerves, and as the result of the actions of an external cause, a knowledge of certain qualities or conditions, not of [… the ] bodies of the nerves of sense themselves;

and these qualities of the nerves of sense are in all different, the nerve of each sense having its own peculiar quality [or energy].

VI. The nerve of each sense seems to be capable of one determinant kind of sensation only, and not of those proper to the other organs of sense;

hence one nerve sense cannot take the place and perform the function of another sense.

VII. The central portions of the nerves included in the encephalon [brain] are susceptible of [the] peculiar sensations [of the nerves], independently of the more peripheral portion of the nervous cords which form the means of communication with the […] organs of sense.

VIII. The immediate objects of the perception of our senses [normally in the real world] are merely particular states induced in the nerves, and felt as sensations either by the nerves themselves or by the sensorium; ...

VIII. [cont’d]… but inasmuch as the nerves of the senses are material bodies, and therefore participate in the properties of matter {generally occupying space, being susceptible of vibratory motion, and capable of being changed chemically as well as by the action of heat and electricity}, they make known to the sensorium, by virtue of the changes thus produced in them by external causes, not [...] their own condition, but [… the] properties and changes of condition of external bodies.

VIII. [cont’d]… The information thus obtained by the senses concerning external nature, varies in each sense, having a relation to the qualities [or energies] of the nerve.

5. epistemic channels [each sense];

external-->nerves-->percept no ESP [27 Feb]; no organ/nerves for ESP

6. no sensory substitution [1 May] blind, deaf ...

7. direct stimulation of the brain --> Conjecture of DuBois-Reymond

8. summary: V --> Molyneux's

paradox III & IV

From VII: Conjecture of DuBois-Reymond(student of Müller’s)

If one could cross-splice the auditory nerve and the optic nerve, would one “see” thunder and “hear” lightning?

William Molyneux, Dioptrica Nova, 1692

Molyneux’s Paradox - the orientation of thevisual fieldRelevant to Müller VIII

Molyneux’s Premise - depth perception

Moylneux’s Conjecture - the blind given sight

From VIII: Molyneux’s Paradox

The image on the back of the retina is upside down and backwards. Why do we not see the world this way?

From VIII: Molyneux’s Paradox

Why do we not see the world as upside and backwards?

2 general answers:1. Brain re-inverts the image. [wrong]2. “The visive faculty takes no notice of its parts, but uses them as an instrument only.” [right]

Psychology 205 Perception

the study of how we know about our world; the study of our bodies, brains, and the functions of our senses;the study of [some of] the roots of knowledge

and culture