Engineering Psychology Cognitive processes perception – sensation – attention – thinking – imagination – memory – creativity – problem solving Jakub Jura Jakub.jura@fs.cvut.cz http://users.fs.cvut.cz/~jura/ing-psych/ What is Cognitive? • From latin cognoscere = getting to know • Distinguish emotional and rational • Descarte’s „Cogito ergo sum“. Mental processes mediate between stimulus and response. Cognitive processes • Base Cognitive processes: – – – – – – – Perception Sensation Attention Thinking Imagination Memory Learning • Advanced Cognitive processes – Creativity – Problem solving Sensation • Sensation is about sense organ and basic processes on this level. • Perception is about creating whole percept. Sensation Perception Visual Perception Auditive Perception Gustatory Perception Olfactory Perception Haptic Perception Proprioception Human Feromon Magnetoception Percept Image Sound Taste Smell Touch on skin Body position Affection / antipathy Impression of north Sence Organ Eye Ear Taste Buds Nose Nociceptors Proprioceptor Vomero-Nasal Organ Unknown Sensation Delusions Lateral Inhibition Efect • Mach’s Strips Negative afterimage Perception • • • • • • Perception is perception of diference. Sensuals limits Gestalt law Multistable figures Invariance in perception Weber–Fechner law Perception Delusionss Which of these circles is bigger? Perception Delusionss • Effect of Contrast Lighter Darker Perception Delusionss Is anything here? Gestalt Laws • Proximity – We tend to group nearby objects. • Similarity – We tend to group objects with similar properties • Closure – We are so accustomed to seeing closure that we sometimes close things that aren't. Gestalt Laws • Good Continuation – We tend to assign objects to an entity that is defined by smooth lines or curves • Pregnantz – We tend to good shape Experiment 2 Multistable perception • Mind separate figure and backgroun. • Unstably between two or more alternative interpretations. • Since you see both, you can’t see both. • Changing may be under control only partially. Invariance in perception • Objects are recognized independent of rotation, translation, scale, elastic deformations, different lighting, and different component features. Neisser's cycle of perception Cognitive Ecology Actual world Object available information Samples Modify Exploration Schema of environment Cognitive map Directs Locomotion and action Weber–Fechner Law • • • • • Psychophysics Ernest Heinrich Weber (1795–1878) Gustav Theodor Fechner (1801–1887) Stimulus Percept Stimulus Sensation Percept Weber • Just noticeable difference (jnd) between two weights was approximately proportional to the mass of the weights • P = k * (S/S) – P … percept – k … constant – S … stimulus Experiment 1 • Dependence of sense impression on the intensity of stimulus 1. Sound Impresion 2. Light Sensum Procedure: a) Set intensity to basic level (L) b) Increase intensity up to one degree (L+1) c) Remember this degree and set intensity up to L+2, L+3, … L+n Weber–Fechner Law • P = k * (S/S) • dP = k * dS/S, • P = k * ln (S/S0) – – – – P … percept k … constant S … stimulus S0 … lower possible stimulus Weber - Fechner