PERCEPTION FINAL

Basic Human Senses

Hearing, sight taste, smell touch

‘Extra’ Human Senses

Balance, pressure, temperature, pain

Perception

how organisms gather and interpret information about environment using senses

Qualia

The subjective, personal aspect of an experience

Sense

A biological mechanism that converts environmental stimuli into neural signals

Transduction

The process of converting outside stimuli, such as light, into neural activity

Doctrine of Specific Nerve Energies

perception is determined by which nerves get stimulated, not how they get stimulated.

Mueller

Who Proposed the Doctrine of Specific Nerve Energies?

70mph

Speed of Neural Conduction

Helmholtz

Who Measured the Speed of Neural Conduction?

Loewi

Who found communication across a synapse?

Sweet, Sour, Salty, Bitter, Umami

Five Basic Tastes

Panpsychism

A belief that all things have minds (or at least some form of consciousness), even plants, rocks, etc 

Solipsism

the view or theory that the self is all that can be known to exist.

Ramon y Cajal

made beautiful illustrations of neurons + noticed synapses 

Ibn al-Haytham

promoted the scientific method, proposed that vision is caused by light ENTERING the eye rather than exiting the eye

Ada Lovelace

She would have loved AI. Wrote the first computer program despite computers not existing.

Ikeda

proposed the fifth taste, umami, and isolated MSG. 

Fechner

founder of the field of psychophysics

Psychophysics

 the study of the relationship between physical quantities (stimuli like lumens of light, grams of sugar molecules, dB of air vibrations, etc.) and psychological quantities (perceptions like brightness, sweetness, and loudness, respectively).

Absolute Threshold

the smallest amount of stimulation that can be detected in psychophysics

Difference Threshold

the change (increase or decrease) a stimulus needs for someone to notice in psychophysics.

Weber’s Law

JND=K*I. The Just Noticeable Difference will be a constant proportion of the original stimulus.

Proprioception

Extra human sense; the position of muscles/ joints

Balance

Extra human sense; movement/ acceleration in the inner ear

Color Vision

What is the perception associated with the wavelength of visible light?

Receptive field

The ‘space’ that a neuron is tuned to; the range, or region, of stimuli that the neuron is responsible for. A cell’s little kingdom that it rules over lol

Just Noticeable Difference

JND in Weber’s Law. The smallest amount of change in perception that can typically be detected.

Operating Range

Paper in starlight (one million) to Paper in sunlight (10 million). The range of stimulation that vision can ‘work’ over.

Accommodation

The fancy technical word for vision focus

Constant

Weber’s Law says the smallest noticeable change is a __________ proportion (%) of the stimulus intensity.

Reflects

A blue shirt looks ‘blue’ because it _______ short (‘blue’) wavelengths of light.

Hyperopia

Corrected with a convex lens

Myopia

Corrected with a concave lens

trichromacy

the ability to see color using three different types of cone cells in the eye

Spectral Reflectance Function

shows the relative amount (%) of reflected light for each wavelength 

short wavelength

blue

medium wavelength

green

long wavelength

red

What is the ‘punchline’ of Young / Helmholtz’s additive color mixing experiments?

you can create any color by just mixing three lights (Red, Green, and Blue)

Why are humans colorblind in the dark?

because our color cones are receptive to wavelengths of light; if there is not enough light, ofc we can’t see color, and our rods take over instead.

Spectral Power Distribution

graph that maps wavelengths coming from a source basically. Usually measured in nanometers of light (wavelength)

Gestalt Motto

The whole is greater than the sum of the parts

Template Matching

A form of object recognition; matching the image of a remembered ’template’, like a mental picture

Structural Description

A form of object recognition, objects are recognized by their parts and their shapes.

Amodal completion

Assumption of a complete object, knowledge of occlusion (something hidden or obscured from view).

Similarity

Closure

Common region

Connectedness

Good continuation

Proximity

Y- junction, arrow junction

where lines meet at a point, that are taken to show corners

T- junction

where one line meets another at a right angle that signal occlusion

Geon

In structural description, these are the ‘parts’ used in object recognition

Topographic Mapping

Neighboring parts of a visual scene are processed by neighboring parts of brain areas.

Cortical Magnification 

the phenomenon where the central part of the visual field (the fovea) gets more ‘real estate’ in the primary visual cortex

What do high spacial frequencies (thin stripes) correspond to?

tests how well a person can see details

Prosopagnosia

AKA facial blindness

Fourier analysis

breaking down images into spatial frequency 'components'/ gratings.

Early level vision

Recognizing colors, shapes, and simple patterns—your eyes getting the raw visual data.

Middle level vision

Putting together shapes into objects, understanding motion, and recognizing faces—making sense of the visual story.

High level vision

Identifying objects, understanding scenes, and recognizing complex patterns—seeing the complete and meaningful story of what you're looking at.

Where/Action Stream

Neural network primarily involved in spatial location and guiding actions. Hand eye coordination. Dorsal brain path

What/Perception Stream

Neural network primarily concerned with identifying and recognizing objects. Ventral brain path

What do low spacial frequencies (big stripes) correspond to?

Tests how well a person can see big features

Additive color mixtures

The mixture of colored light wavelengths

Accommodation 

the process by which the eye's lens changes shape to focus near or far objects on the retina

Vergence

the simultaneous movement of the pupils of the eyes toward or away from one another during focusing.

Here’s a PVC receptive field:  |-|+|-|. What pattern of light has the best chance of increasing the cell’s response?

A vertical pattern of light

Deciding whether you are looking at a tree or a cat is probably done based on...

Structural description

“Ganglion / PVC cells are each responsible for a particular area on the retina”. This fact describes...

Receptive fields

If a trichromatic person sees a surface that reflects all visible wavelengths equally, it will appear…

White

A Spectral Reflectance Function is determined by...

the material that an object is made out of

Let’s say you take an image, and do a Fourier analysis into gratings. Now, throw away all the high spatial frequency gratings, then combine all the leftover gratings. The image will now look...

Blurrier

color vision

The ability to distinguish different wavelengths of light, due to the presence of one or more types of cone receptors in the eye

optic chiasm

allows the brain to process binocular vision by partially crossing optic nerve fibers

superior colliculus

a structure in the midbrain that integrates sensory info

Non-pictorial depth cues

the ones that are NOT the classic pictorial ones (like occlusion, linear perspective, relative size, etc.)

Accommodation

A depth cue that is based on the focusing of the crystalline lens. Lets us focus on things that are near/far.

Vergence

A depth cue when depth is estimated from the convergence (pointing inward) or divergence (pointed outward) of the two eyes

Stereopsis

This is when the brain uses binocular disparity to gauge depth.

Stereopsis

Which cue is the most precise (it’s added in 3D movies)

Accommodation and Vergence

Which depth cues are based on oculomotor cues?

Depth Perception

The ability to estimate the distances (‘depth’) of surfaces

Occlusion

Whatever is doing the ‘covering’ is nearer, whatever is being covered is farther

Linear perspective/ Texture Gradient

More convergence and/or denser texture means farther

Aerial Perspective

Hazier / lower contrast / “bluer” means farther (clearer/sharper means nearer)

Familiar size

Bigger means nearer, smaller means farther

Relative Size

Bigger means nearer (smaller, farther); higher means farther (lower, nearer)

Binocular disparity

the difference in the image each eye receives due to the horizontal separation of the eyes

3D Perception

Which comes first: object recognition or 3D perception?

Bela Julesz

Who proved/ researched the ‘object recognition vs. depth perception’?

Saccadic eye movements

reading, walking, driving, etc. (fast jerks from one fixation to another, 3-5 per second)

Smooth Pursuit eye movements

tracking a flying ball, a bird, or a person crossing the street

Vergence eye movements

eyes turn inward or outward to keep something on the fovea of both eyes (e.g., looking at something getting closer or farther)

Exogenous attentional selection

When our attention is ‘grabbed’ by something (bright light, sudden movement

Overt attentional selection

when a person looks where they are attending (eye movements go to the target)

Covert attentional selection

when someone attends to something “out of the corner of their eye” without looking at it

Hemineglect

When a person physically can not pay attention to left halves of objects due to brain lesions