Sensory and Perception
Action potentials are all or nothing, so strong stimulus produces more action potentials NOT bigger ones.
The neurotransmitters being released from the presynaptic neuron trigger the action potential in the post-synaptic neuron.
Sensation: the basic processes by which sensory organs and the nervous system respond to stimuli in the environment and the elementary psychological experiences that result from these processes.
Perception: the more complex organizing of sensory information within the brain and the meaningful interpretations extracted from it.
Physical stimulus: the matter of energy of the physical world that impinges on sense organs.
Sensory receptors: specialized structures that respond to physical stimuli by producing electrical changes that can initiate neural impulses in sensory neurons
Have their neural pathways in the brain
Have their type of receptors
Sensory neurons: spec-lined neurons that carry information from sensory receptors into the central nervous system
Sensory Transduction: when a receptor cell produces an electrical charge in response to physical stimulation.
The process by which receptors in the eye respond to light, receptors in the ear respond to sound, etc.
Sensory adaptation: the change in sensitivity that occurs when a given set of sensory receptors and neurons is either strongly stimulated or relatively unstimulated for a length of time.
Can be mediated by receptor cells or by the central nervous system
Receptor potential and rate or action potentials are reduced
Senses are much more responsive to charging than unchanging stimulation
The stimuli for smell are molecules that evaporate into the air, are taken into the nasal cavity, and then become dissolved in mucous guild covering that olfactory epithelium.
Olfactory epithelium: contains roughly 6 mil olfactory sensory neurons
Each is sensitive and contains 5-20 hairlike cilia
Age:
Smell declines with age; elderly complain of lost taste but is a loss of smell
Gender:
Women are generally more sensitive to smell and become more sensitive to specific odors with increased exposure
This applies to women in reproductive years, not pre-pubescent, or post-menopausal women
Mother-infant bonding: both mothers and newborns can identify each other based on smell alone
Choosing a genetically compatible mate: many species prefer a mate that smells most opposite of them
Pheromone: a chemical substance that is released by an animal, and acts on the members of its species to promote some specific behavioral or psychological response.
Most mammals have a vomeronasal organ which contains receptor cells specialized for responding to pheromones
Mixed findings on humans’ susceptibility to pheromones
Odorants: a substance giving off a smell, that can enter through the nostrils or the mouth.
Nasopharynx: opening in the back of the mouth which connects the nasal cavity
Chewing and swallowing pushes odorants into the nasal cavity
Flavor: consists of true taste as well as smell. We experience flavor as coming only from our mouth
Pinching nostrils and closing eyes will mostly make it nearly impossible to distinguish flavor in most foods
Anatomy and Physiology:
2/3 of taste buds are on the tongue and the rest are on the roof of the mouth and the throat
Specialized taste receptor cells are on the taste buds
Can trigger neural impulses in taste sensory neurons, which send input to the primary taste areas in the frontal lobe and other parts of the brain
Six primary taste/receptor cells include; sweet, sour, fat, umami, bitter, and salty.
Generally, pleasant and unpleasant tastes correlate to nutritional and non-nutritional foods for our ancestors living in more natural, non-sedentary, environments
Salt balances bodily fluids, sugar provides energy, and protein builds tissues
Decaying matter tastes sour, and plant and animal toxins taste bitter
Women are more sensitive to bitter tastes in the first three months. During pregnancy, when the fetus is most vulnerable to poisons
Children’s extra sensitivity may have helped early development
Somatosense: we experience pain coming from our bodies, not the world.
Nociceptors: free nerve endings of pain sensory neurons located in many parts of the body
Free nerve endings: sensitive nerve terminals throughout the body
C fibers and A-delta fibers: two types of pain sensory neurons mediate two different waves of pain
Fast “first” pain travels along the myelinated A-delta fibers, and slow “second” pain travels along C fibers
Brain areas for three components of pain experience:
The sensory component which depends largely on the sotomasensory cortex
The primary emotional and motivational component depends on the person’s limbic system
The secondary emotional and motivating component is suffering that derives from the person’s worrying about the future or about the meaning of the pain
Walls Gate-Control Theory of Pain: Pain depends on the degree to which pain input can pass through a gate to the CNS that enters the brain stem
Can be mediated by learned and unlearned stimulus information coming down from the brain to the brainstem
Increased pain sensitivity after the injury occurs at the injury site as well as the CNS gate
Outer Ear: receives and funnels sound waves towards the structure where transduction occurs
Pinna: a flap of skin and cartilage forming the visible portion of the ear
Pitch perception: the aspect of hearing that allows us to tell how high or low a given tone is
High frequencies stimulate the proximal end of the basilar membrane
Low frequencies stimulate the distal end
Conduction deafness: ossicles become rigid and cannot carry sounds inward from the tympanic membrane to the cochlea
Conventional hearing aids can help
Receptors: 130 million photoreceptors embedded in your retina
Converts light into neural activity
Rods: insensitive to color, mostly responsible for peripheral vision and mission at night
Cones: color sensitive, responsible for clear vision
The light shines into the eye through the lens, the clear opening inside the iris
Psychophysics: the study of relationships between physical characteristics stimuli and sensory experience produces by those stimuli
Not interested in physiology
Absolute threshold: the faintest debatable stimulus of any type of stimulus
Difference threshold: the minimal difference in magnitude between two stimuli that are required for the person to detect them as different
Action potentials are all or nothing, so strong stimulus produces more action potentials NOT bigger ones.
The neurotransmitters being released from the presynaptic neuron trigger the action potential in the post-synaptic neuron.
Sensation: the basic processes by which sensory organs and the nervous system respond to stimuli in the environment and the elementary psychological experiences that result from these processes.
Perception: the more complex organizing of sensory information within the brain and the meaningful interpretations extracted from it.
Physical stimulus: the matter of energy of the physical world that impinges on sense organs.
Sensory receptors: specialized structures that respond to physical stimuli by producing electrical changes that can initiate neural impulses in sensory neurons
Have their neural pathways in the brain
Have their type of receptors
Sensory neurons: spec-lined neurons that carry information from sensory receptors into the central nervous system
Sensory Transduction: when a receptor cell produces an electrical charge in response to physical stimulation.
The process by which receptors in the eye respond to light, receptors in the ear respond to sound, etc.
Sensory adaptation: the change in sensitivity that occurs when a given set of sensory receptors and neurons is either strongly stimulated or relatively unstimulated for a length of time.
Can be mediated by receptor cells or by the central nervous system
Receptor potential and rate or action potentials are reduced
Senses are much more responsive to charging than unchanging stimulation
The stimuli for smell are molecules that evaporate into the air, are taken into the nasal cavity, and then become dissolved in mucous guild covering that olfactory epithelium.
Olfactory epithelium: contains roughly 6 mil olfactory sensory neurons
Each is sensitive and contains 5-20 hairlike cilia
Age:
Smell declines with age; elderly complain of lost taste but is a loss of smell
Gender:
Women are generally more sensitive to smell and become more sensitive to specific odors with increased exposure
This applies to women in reproductive years, not pre-pubescent, or post-menopausal women
Mother-infant bonding: both mothers and newborns can identify each other based on smell alone
Choosing a genetically compatible mate: many species prefer a mate that smells most opposite of them
Pheromone: a chemical substance that is released by an animal, and acts on the members of its species to promote some specific behavioral or psychological response.
Most mammals have a vomeronasal organ which contains receptor cells specialized for responding to pheromones
Mixed findings on humans’ susceptibility to pheromones
Odorants: a substance giving off a smell, that can enter through the nostrils or the mouth.
Nasopharynx: opening in the back of the mouth which connects the nasal cavity
Chewing and swallowing pushes odorants into the nasal cavity
Flavor: consists of true taste as well as smell. We experience flavor as coming only from our mouth
Pinching nostrils and closing eyes will mostly make it nearly impossible to distinguish flavor in most foods
Anatomy and Physiology:
2/3 of taste buds are on the tongue and the rest are on the roof of the mouth and the throat
Specialized taste receptor cells are on the taste buds
Can trigger neural impulses in taste sensory neurons, which send input to the primary taste areas in the frontal lobe and other parts of the brain
Six primary taste/receptor cells include; sweet, sour, fat, umami, bitter, and salty.
Generally, pleasant and unpleasant tastes correlate to nutritional and non-nutritional foods for our ancestors living in more natural, non-sedentary, environments
Salt balances bodily fluids, sugar provides energy, and protein builds tissues
Decaying matter tastes sour, and plant and animal toxins taste bitter
Women are more sensitive to bitter tastes in the first three months. During pregnancy, when the fetus is most vulnerable to poisons
Children’s extra sensitivity may have helped early development
Somatosense: we experience pain coming from our bodies, not the world.
Nociceptors: free nerve endings of pain sensory neurons located in many parts of the body
Free nerve endings: sensitive nerve terminals throughout the body
C fibers and A-delta fibers: two types of pain sensory neurons mediate two different waves of pain
Fast “first” pain travels along the myelinated A-delta fibers, and slow “second” pain travels along C fibers
Brain areas for three components of pain experience:
The sensory component which depends largely on the sotomasensory cortex
The primary emotional and motivational component depends on the person’s limbic system
The secondary emotional and motivating component is suffering that derives from the person’s worrying about the future or about the meaning of the pain
Walls Gate-Control Theory of Pain: Pain depends on the degree to which pain input can pass through a gate to the CNS that enters the brain stem
Can be mediated by learned and unlearned stimulus information coming down from the brain to the brainstem
Increased pain sensitivity after the injury occurs at the injury site as well as the CNS gate
Outer Ear: receives and funnels sound waves towards the structure where transduction occurs
Pinna: a flap of skin and cartilage forming the visible portion of the ear
Pitch perception: the aspect of hearing that allows us to tell how high or low a given tone is
High frequencies stimulate the proximal end of the basilar membrane
Low frequencies stimulate the distal end
Conduction deafness: ossicles become rigid and cannot carry sounds inward from the tympanic membrane to the cochlea
Conventional hearing aids can help
Receptors: 130 million photoreceptors embedded in your retina
Converts light into neural activity
Rods: insensitive to color, mostly responsible for peripheral vision and mission at night
Cones: color sensitive, responsible for clear vision
The light shines into the eye through the lens, the clear opening inside the iris
Psychophysics: the study of relationships between physical characteristics stimuli and sensory experience produces by those stimuli
Not interested in physiology
Absolute threshold: the faintest debatable stimulus of any type of stimulus
Difference threshold: the minimal difference in magnitude between two stimuli that are required for the person to detect them as different