Introduction to Psychology: Sensation and Perception PDF

# Introduction to Psychology: Sensation and Perception ### Sensation and Perception - A diagram of a human head with the brain in the middle. Around the brain are several sensory organs like the eye, ear, nose, mouth, and hand. ### "Sensation and Perception" Short Film Project A Facebook reel...

# Introduction to Psychology: Sensation and Perception ### Sensation and Perception - A diagram of a human head with the brain in the middle. Around the brain are several sensory organs like the eye, ear, nose, mouth, and hand. ### "Sensation and Perception" Short Film Project A Facebook reel link with a description: - The topic: "Sensation and Perception" - a two-minute "Quarantined" short film project in Introduction to Psychology. - Description: One of the Outstanding Performance from my BS PSYCHOLOGY student 1A (Group 1). - Objective: to connect students, gain friends while staying home and reflect what they have learned. ### Alan Watts Quote - "Every living atom within all matter is collecting data and telling a story, and all is interconnected. To witness the actuality of reality is to listen and feel every sensation. The deeper eye innerstand and connect with All that IS, the broader my perception and awareness becomes." - "We see what we believe rather than what we see" ### Sensation and Perception Overview - This module will provide an overview of how sensory information is received and processed by the nervous system and how that affects our conscious experience of the world. - We begin by learning the distinction between sensation and perception. - Then we consider the physical properties of light and sound stimuli, along with an overview of the basic structure and function of the major sensory systems. ### Sensing and Perceiving - Sensing and Perceiving are two separate processes that are very closely related. - You have probably known since elementary school that we have five senses. - Vision. - Hearing (audition). - Smell (olfaction). - Taste (gustation). - Touch (somatosensation). - There are more senses than just the five most commonly known. Other senses include: - Balance (the vestibular sense). - Body position and movement (proprioception and kinesthesia). - Pain (nociception). - Temperature (thermoception). ### Sensation - Resulting from the stimulation of a sense organ (physiological basis of perception) - **Sensory Information:** Includes vision, hearing, smell, taste, touch, balance, body position, movement, pain, and temperature - **Absolute Threshold (ATL):** The lowest intensity of a stimulus that a person notices at least 50% of the time - **Subliminal Messages:** Messages that are presented below the threshold for conscious awareness - **Difference Threshold:** The least difference between two stimuli that a person can notice. ### Perception - Perception is the organization, interpretation of sensations and consciously experienced. - Sensation is a physical process whereas perception is psychological - **Attention and motivation** determine what is sensed versus what is perceived. - **Signal detection theory:** Shows the ability to identify a stimulus when it is embedded in a distracting background. - **Sensory adaptation:** we don't perceive stimuli that remain relatively constant over prolonged periods of time. ## Anatomy of Vision - **Cornea:** The transparent covering over the eye. It serves as a barrier between the inner eye and the outside world, and it is involved in focusing light waves that enter the eye. - **Pupil:** The small opening in the eye through which light passes, and the size of the pupil can change as a function of light levels as well as emotional arousal. - **Iris:** The muscles that are connected to the iris (colored portion of the eye) control the pupil's size. - **Retina:** The light-sensitive lining of the eye. - **Fovea:** A small indentation in the back of the eye - **Optic nerve:** Carries visual information from the retina to the brain. ### Eye Abnormalities - **Myopia (nearsightedness):** - People with Myopic vision usually have eyeballs that are too large for their lens and cornea to focus light properly on their retina. - Eyeglasses and contact lenses can usually correct this problem. - **Hyperopia (farsightedness):** - Hyperopia vision is caused by the eyeball being too small for the lens and cornea to focus light properly on the retina. - Eyeglasses and contact lenses can usually correct this problem. - **Presbyopia (aging eyes):** - As people age, they often begin to have difficulty focusing their eyes for reading or close work. - It is usually corrected with reading glasses. Some people may need bifocal or trifocal lenses. - **Astigmatism (distorted vision):** - People with Astigmatism have irregularly shaped corneas. - It is usually corrected with eyeglasses or contact lenses. - **Ocular Albinism:** - With this inherited birth defect, people have no pigment or reduced pigment in their eyes, skin and hair. - This pigment called melanin is needed for the full development of the retina. - Children with this condition have mild to sever vision loss and are very light sensitive. - **Strabismus:** - In childhood, it is often noticed within weeks of birth. - Older children may complain of double vision. - It can be confirmed by asymmetrical light reflections from the eyes. - **Congenital ptosis:** - In ptosis, the upper eyelid of one or both eyes 'droops'. - If the lid covers the pupil, it can interfere with vision. - A torticollis can develop if the head is tilted to maintain binocular vision. - If a ptosis develops gradually or without a family history, a full examination and neurological check are required. ## Anatomy of the Auditory System - A diagram showing the three parts of the ear. - **Outer ear:** includes the pinna, which is the visible part of the ear that protrudes from our heads, the auditory canal, and the tympanic membrane, or eardrum. - **Middle ear:** contains three tiny bones known as the ossicles, which are named the malleus (or hammer), incus (or anvil), and the stapes (or stirrup). - **Inner ear:** contains the semi-circular canals, which are involved in balance and movement (the vestibular sense), and the cochlea. The cochlea is a fluid-filled, snail-shaped structure that contains the sensory receptor cells (hair cells) of the auditory system. ### Types of Hearing Loss - Deafness - Congenital deafness - Conductive hearing loss - Sensorineural hearing loss ### Factors Affecting Hearing Loss - Age. - Noise. - Genes. - Illness. - Chemicals. ## Touch - Specific receptors in the skin convert stimulation to electrical nerve impulses, a process called transduction. - **Mechanoreceptors:** Respond to mechanical stimuli, such as stroking, stretching, or vibration of the skin. - **Thermoreceptors:** Respond to cold or hot temperatures. - **Chemoreceptors:** Respond to certain types of chemicals either applied externally or released within the skin. ## Somatic Sensation - Sensations arising from the skin — such as touch, pressure, cold, warmth, and pain — and from the muscles, tendons, and joints — such as the position of the limbs and pain — are known as somatic sensations. - Soma, the Greek word for body, refers to the whole of the body structure, apart from the germ cells (eggs and sperm). - Sensations arising from the internal organs (the viscera) - such as pain or the sense of fullness of the stomach or bladder, may therefore be included, although they are usually considered separately as visceral sensations. - Pain arising from the viscera is often felt as though it comes from some part of the body surface or underlying tissue (referred pain). ### Somatic Impairment - Acne - Athletes foot - Birthmarks - Cysts - Dry skin - Stretch mark - Varicose veins ## Gustatory Sensation - The tongue contains nearly two thousand taste buds, although they are also located in small numbers in the soft palate and in the throat. - On the tongue, taste buds are located on bumps of connective tissue called papillae. - Circumvallate or vallate papillae are the largest of these, found on the posterior part of the tongue. - Fungiform papillae are found on the tip and sides of the tongue. - Filiform are on the majority of the tongue. - To be tasted, substances must be suspended in saliva, and an interaction occurs which creates a nerve impulse. - There are four primary tastes: sour, salt, sweet, and bitter. ### Gustatory Impairment - **Leukoplakia:** This condition causes cells in the mouth to grow excessively. This leads to the formation of white patches inside the mouth, including on the tongue. Although not dangerous on its own, leukoplakia can be a precursor to cancer. - It is important for your dentist to determine the cause of white patches on your tongue. - Leukoplakia can develop when the tongue has been irritated, and it is often found in people who use tobacco products. - **Tongue Movement Disorders:** Tongue movement problems are most often caused by nerve damage. Tongue movement disorders may result in: - Breastfeeding problems in newborns; - Difficulty moving food during chewing and swallowing; and - Speech difficulties. - **Hairy Tongue:** It is a harmless condition in which the tongue looks hairy or furry. The disorder usually goes away with antibiotics. - **Black Tongue:** Sometimes the upper surface of the tongue turns black or brown in color. This is an unsightly condition but it is not harmful. - **Smooth Tongue:** Causes include Anemia and Vitamin B12 deficiency. ## Olfaction - **Nasal cavity:** The space behind the nose where air that we breathe passes. - **Nostrils:** Two holes of the nose where the air gets inside. - **Olfactory nerve:** Transmits the sense of smell from the nasal cavity to the nose. - **Hard Palate:** Bones separate the oral cavity from the nasal cavity. - **Soft palate:** Closes the nasal cavity from the oral cavity when swallowing. ### Olfactory Impairment - **Anosmia** - inability to smell - **Dysosmia** - things smell different than they should - **Hyposmia** - decreased ability to smell - **Olfactory Reference Syndrome:** A psychological disorder which causes the patient to imagine he has strong body odor - **Parosmia** - things smell worse than they should - **Phantosmia** - "hallucinated smell," often unpleasant in nature ## Quick Review - What is the difference between sensation and perception? - How does vision work? - How do people see color and depth? - How does hearing work? - What are the basic anatomy and functions of taste, smell, touch, pain, and the vestibular sense? - What is perception? - What are some examples of gestalt principles and multimodal perception?