Sensations are the processes through which sensory organs/receptor cells detect stimuli, and transduction is the conversion of stimuli into neural impulses. On the other hand, perceptions are the processes through which sensory information is interpreted, understood, and organized.
Psychophysics
Psychophysics is the branch of psychology that studies how sensory stimuli change thoughts/behaviors. It was first studied by Wundt. Absolute threshold is defined as the smallest amount of a stimulus a person can detect, while difference threshold is the smallest amount of change in a stimulus that a person can detect. Ernest Weber came up with Weber's Law, which states that the greater the magnitude or intensity of a stimulus, the more that stimulus must change before a person can notice it's different. Selective attention, on the other hand, is the ability to focus upon one stimulus, from among all surrounding environmental stimuli. This ability is influenced by various variables such as goal-directed attention, change blindness, and stimulus-driven capture.
Adaptive Sensory Adaptation
Adaptive sensory adaptation is an important factor that might indicate danger, allowing for a rapid response to potentially life-saving stimuli. Sensory adaptation, on the other hand, is the process through which the longer a person is exposed to an unchanging stimulus, the less likely they are to detect it. This adaptation frees attention for the detection of new stimuli, which have the potential to signal danger.
Cognitive Factors and Ability to Detect Stimuli
The ability to detect stimuli is influenced by factors such as the intensity of the stimulus, selective attention factors, and the cognitive state of the person detecting the stimulus. The Signal Detection Theory states that a person's emotional state, expectations, and decision-making processes affect whether they detect a stimulus or not.
Vision
The McGurk Effect (1976) is a phenomenon where what is seen can alter what is heard. The anatomy of the eye plays a crucial role in vision. The general function of the eye's anatomy is to channel light toward the retina. The pathway of light through the eye involves the cornea, pupil, and iris, all of which play essential roles in the process of vision.
Structure of the Eyeball
The eyeball's structure, including the cornea, pupil, iris, lens, retina, and optic nerve, all contribute to the process of vision. In the retina, transduction occurs, and photoreceptors (cones/rods receptors) are the first level of cells in the retina. The cones are activated by colors and bright light, while the rods are activated by low light.
Theories of Color Vision
Theories of color vision, such as the Trichromatic Theory and Opponent Process Theory, help in understanding how color vision works and why colorblind people have difficulty distinguishing colors.
Auditory Sense
Sound localization and the cocktail party effect are essential components of auditory perception, enabling individuals to determine the origin of a sound and focus attention on particular sounds while filtering out others.
Types of Perception
Different types of perception, such as depth perception, motion perception, and constancy, play crucial roles in how individuals perceive the world around them.
In conclusion, sensations and perceptions in psychology are complex and multi-faceted processes that involve various sensory stimuli, adaptive responses, cognitive factors, and anatomical structures, all of which contribute to our understanding of the world around us.
