PSYC 1020 Y Sensing and Perceiving I Dr

Sensing States & Events: External versus Internal Movement Conscious elaboration & thought Skin sensation

External States & Events Skin Senses Vision Touch, Temperature, Pressure, Pain Hue, Brightness, Saturation

Extrasensory Perception: Phenomena in Science or Pseudoscience? ? ? !

Extrasensory Perception: Charles Darwin’s Scepticism Thought Transference (1870 s) For: Alfred Russel Wallace Against:

Internal States & Events Proprioception & Kinaesthesis Sensations of body/limb/muscle position & movement Interoception

Psychophysics & Measurement Stimulus to Conscious Experience Psychophysical Relationship

Classical Psychophysics Absolute Thresholds Sensory Modality Detection Threshold (Limen) Vision A candle flame at

Difference Thresholds Just Noticeable Differences (JND) L 1 + D L WEBER’s LAW where

Thresholds & Decisions Signal Detection Theory (SDT) Response/Decision Stimulus Reality Same/Present Diff/Absent Same/Present HIT

Subliminal Perception? A case study for SDT Key Words Motivation Mental Set Perceptual Defence

The Stimulus for Vision Electromagnetic Radiation Visible Light Spectrum 400 – 700 nanometres (10

The Eye Anatomy & Physiology Retina (photosensitive rods & cones) Pupil Fovea (central vision)

Retinal Rods and Cones Rods 6. 0 300 x 5. 0 4. 0 7.

Retina to Brain Central Visual Pathway Corpus Callosum Cerebellum Thalamus Brodmann Areas 17, 18,

Basic Visual Functions: Everyday Tests of Visual Acuity Snellen Chart E BN RKF V

Optical Disorders: Focussing the image Enmetropic (normal acuity) Myopic (nearsightedness) Hyperopic (farsightedness) Astigmatic (Blurring

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PSYC 1020 Y Sensing and Perceiving I Dr. Jack Broerse Sense Modalities Psychophysics Light, Eye & Brain Internet : http: // www. psy. uq. edu. au

Sensing States & Events: External versus Internal Movement Conscious elaboration & thought Skin sensation Visual elaboration Auditory sensation Perceptual judgement Body sensation (cerebellum) Visual sensation (visual cortex)

External States & Events Skin Senses Vision Touch, Temperature, Pressure, Pain Hue, Brightness, Saturation (Density) Burned Putrid Flowery Spicy Fruity Resinous Audition Volume, Frequency, Tonal Quality (Density) Bitter Sour Salty Sweet Taste & Smell

Extrasensory Perception: Phenomena in Science or Pseudoscience? ? ? !

Extrasensory Perception: Charles Darwin’s Scepticism Thought Transference (1870 s) For: Alfred Russel Wallace Against: Charles Darwin Thomas H. Huxley (see Scientific American, October, 1996).

Internal States & Events Proprioception & Kinaesthesis Sensations of body/limb/muscle position & movement Interoception Vague sensations of internal organs & deep pain

Psychophysics & Measurement Stimulus to Conscious Experience Psychophysical Relationship

Classical Psychophysics Absolute Thresholds Sensory Modality Detection Threshold (Limen) Vision A candle flame at 60 km on clear dark night Hearing A watch ticking at 6 m in quiet conditions Touch Wing of a bee falling on your cheek from 1 cm Smell One eye drop of perfume in 3 -room appartment Taste One teaspoon sugar in 10 litres water

Difference Thresholds Just Noticeable Differences (JND) L 1 + D L WEBER’s LAW where DL L Discriminations: Same vs Different =DL = Constant L 2 + D L

Thresholds & Decisions Signal Detection Theory (SDT) Response/Decision Stimulus Reality Same/Present Diff/Absent Same/Present HIT FALSE ALARM Diff/Absent MISS CORRECT REJECTION Key Words Sensitivity vs Decision Criterion Hits – False Alarms

Subliminal Perception? A case study for SDT Key Words Motivation Mental Set Perceptual Defence

The Stimulus for Vision Electromagnetic Radiation Visible Light Spectrum 400 – 700 nanometres (10 -9 m) Wavelength (l) Amplitude l = 10 15 m Frequency= 1/l l = 10 7 m – 10 13 m

The Eye Anatomy & Physiology Retina (photosensitive rods & cones) Pupil Fovea (central vision) Lens Blind Spot Cornea Iris Optic Nerve Approx. 9 cm at normal viewing distance +

Retinal Rods and Cones Rods 6. 0 300 x 5. 0 4. 0 7. 0 Log. Threshold Log. Relative Sensitivity & Dark Adaptation Cones 3. 0 2. 0 1. 0 6. 0 Cones 5. 0 4. 0 3. 0 Rods 2. 0 400 500 600 700 Wavelength (nm) 1. 0 10 20 30 40 Minutes in Dark 50

Retina to Brain Central Visual Pathway Corpus Callosum Cerebellum Thalamus Brodmann Areas 17, 18, 19 Visual Cortex

Basic Visual Functions: Everyday Tests of Visual Acuity Snellen Chart E BN RKF V M WX L C Landolt ‘C’

Optical Disorders: Focussing the image Enmetropic (normal acuity) Myopic (nearsightedness) Hyperopic (farsightedness) Astigmatic (Blurring in some axis) Presbyopic (Accomodation problems)