PSYC*3270 Week 5 Flashcards
Is bottom-up or top-down processing based on incoming stimuli from the environment?
Bottom-up
What is data-based processing also known as?
Bottom-up processing
Is bottom-up or top-down processing based on the perceiver’s knowledge?
Top-down
What is knowledge-based processing also known as?
Top-down processing
What are the nine steps of perception?
- Environmental stimulus
- Attended stimulus
- Stimulus on receptors
- Transduction
- Transmission
- Processing
- Perception
- Recognition
- Action
How can the nine steps of perception be divided?
Intro three categories of three:
- Stimulus
- Electricity
- Experience and action
What are four common features involved in processing across senses?
All senses have:
- Specialized receptor cells
- Primary, secondary, and tertiary sensory neurons
- Primary and secondary sensory areas
- Association areas
What is the simplest type of sensory receptor?
A neuron with naked/free nerve endings
Are nociceptors considered to be simple or complex sensory receptors?
Simple
Are neural receptors with nerve endings encased in connective tissue capsules considered to be simple or complex?
Complex
T or F: Most special senses receptors are cells that release NTs onto sensory neurons, initiating an action potential.
True
What is the primary difference between neural and non-neural receptors?
- Neural: Can generate action potentials
- Non-neural: Cannot generate action potentials
T or F: Non-neural receptors can generate graded potentials.
True
Which type of receptor respond to chemical ligands?
Chemoreceptors
Which type of receptor respond to mechanical energy?
Mechanoreceptors
Which type of receptor respond to temperature?
Thermoreceptors
Which type of receptor respond to light?
Photoreceptors
What are the four main properties of sensory receptors?
- Threshold
- Range
- Adaptation
- Acuity
In terms of the properties of sensory receptors, what does “threshold” refer to?
Receptors don’t activate until a certain threshold of stimulation is reached
In terms of the properties of sensory receptors, what does “range” refer to?
Each sensory modality has a limited range of stimuli it can respond to
In terms of the properties of sensory receptors, what does “adaptation” refer to?
The adjustment of the receptor’s sensitivity based on the current environment
In terms of the properties of sensory receptors, what does “acuity” refer to?
The ability to distinguish between stimuli within a certain sensory modality
What are three factors that can influence the fate of a certain sensory stimulus?
- Attention
- Memory
- Emotion
Do ascending or descending pathways travel from the spinal cord, to subcortical regions, to cortical regions?
Ascending
Do ascending or descending pathways travel from the cortex, to subcortical regions, to the spinal cord?
Descending
What is the result of simultaneous activation of ascending and descending pathways?
Multisensory integration
Where does the majority of multisensory integration occur?
The thalamus and cortex
What are the five sensory systems?
- Olfaction
- Gustation
- Somatosensation
- Audition
- Vision
What is anosmia?
The loss of ability to smell
What is the oldest and most conserved sense across species and evolution?
Olfaction
The transduction of energy from what type of molecule leads to the activation of olfactory receptors?
Odourants
What is the neural pathway for olfaction (six steps)?
- Primary bipolar neurons
- Glomeruli
- Secondary neurons
- Primary olfactory cortex
- Secondary olfactory cortex
- Connections to other areas
What are glomeruli?
Collection of synapses between primary and secondary neurons
What is the primary olfactory cortex also known as?
The pirifrom cortex
What role does the piriform cortex play in olfaction?
Helps detect odours
In which lobe is the secondary olfactory cortex?
The orbitofrontal lobe
What role does the secondary olfactory cortex play in olfaction?
Helps identify odours
What are two ways in which the olfactory pathway is unique?
- Most of the olfactory nerve axons project to the ipsilateral (rather than contralateral) cortex
- The olfactory nerve arrives at the primary olfactory cortex without passing through the thalamus
T or F: Much of what we perceive as taste is actually smell?
True
What are four functions of the papillae on the tongue?
- Gustation
- Sensation
- Proprioception
- Enzyme secretion
T or F: Papillae on the tongue can detect both nociception and temperature.
True
What are the five basic tastants?
- Salty (Na+)
- Sour (acidic/ H+)
- Sweet (nutrient/caloric value/ ex. glucose)
- Bitter (ex. nicotine)
- Umami (savoury/ ex. glutamate)
The transduction of energy from what type of molecule leads to the activation of gustatory receptors?
Tastant
Which two tastants act upon ionotropic receptors?
Salty and sour (remember because Na+ and H+ are ions)
Which three tastants act upon metabotropic receptors?
- Sweet
- Bitter
- Umami
Are taste receptor cells neural or non-neural?
Non neural
T or F: Tase receptor cells are specialized receptor cells.
True
How do taste ionotropic receptor cells transduce information to the primary gustatory neurons?
By releasing serotonin into the synaptic cleft
How do metabotropic receptor cells transduce information to the primary gustatory neurons?
By releasing ATP into the synaptic cleft
What is the neural pathway for gustation? (seven steps)
- Taste receptor cells
- Primary bipolar neurons
- Chroda tympani nerve
- Ventral posterior medial nucleus of the thalamus
- Primary gustatory cortex
- Secondary gustatory cortex
- Connection to other areas
Where is the primary gustatory cortex located?
In the insula and operculum
In which lobe is the secondary gustatory cortex?
The orbitofrontal lobe
In which brain region does the integration of tase and smell occur?
The orbitofrontal lobe (secondary olfactory and gustatory cortex)
What are the four main somatosensory modalities?
- Proprioception
- Temperature
- Nociception
- Touch
Pressure, vibration, stretch, texture, and fluttering/stroking, are registered by which type of receptor?
Mechanoreceptor
T or F: Somatosensory receptors are primary bipolar neurons.
True
What is the neural pathway for somatosensory? (six steps)
- Primary bipolar neurons
- Secondary sensory neurons
- Tertiary sensory neurons
- Primary somatosensory cortex
- Secondary somatosensory cortex
- Connections to other areas
What are the two types of somatosensory pathways?
- Medial lemniscus
- Spinothalamic
Fine touch, proprioception, and vibration are processed through which somatosensory pathway?
The medial lemniscus pathway
Where do secondary sensory neurons in the medial lemniscus pathway cross the midline of the body?
The medulla
Irritants, temperature, and coarse touch are processed through which somatosensory pathway?
The spinothalamic pathway
Where do secondary sensory neurons in the spinothalamic pathway cross the midline of the body?
The spinal cord
Where are tertiary sensory neurons located?
The thalamus
In which lobe are the primary and secondary somatosensory cortices located?
The parietal lobe
T or F: Somatosensory pathways are not dissociable, meaning it is not possible to have impairments in one but not the other.
False. They are dissociable.
What are the two ways in which sound waves are distinguished?
- Frequency
- Amplitude
What does the number of sound wave peaks per second measure?
Frequency
Is sound frequency measured in Hertz or decibels?
Hertz
Is the frequency of sound an interpretation of pitch or intensity?
Pitch
What does the amplitude/height of sound wave peaks measure?
Loudness
Is sound loudness measured in Hertz or decibels?
Decibels
Is the loudness of sound an interpretation of pitch or intensity?
Intensity
What are the two computational goals of audition?
- Determine what is being heard
- Determine where a sound is coming from
What is the interaural time?
The difference in time between when a sound reaches each of the two ears
What does intraural time provide information about?
The location of a sound
What are the three main divisions of the ear?
- External ear
- Middle ear
- Inner ear
What is the role of the pinna in the external ear?
Direct sound waves into the ear
Is the external ear fluid or air filled?
Air
Which structure divides the external and middle ear?
The tympanic membrane (ear drum)
What are the three tiny bones in the middle ear?
- Malleus
- Incus
- Stapes
Is the middle ear air or fluid filled?
Air
What are the two structures that separate the middle and inner ear?
- Oval window
- Round window
What type of information is processed by the semicircular canals of the inner ear?
Where the head is in space
What role does the eustachian tube play in audition?
Allows the pressure from the ear to equilibrate
How many energy transductions are involved in sound transmission through the ear?
Five
What are the five energy transductions that occur during sound transmission?
- Sound waves → vibrations (occurs at tympanic membrane)
- Vibrations of external ear → stronger vibrations in middle ear
- Vibrations → fluid waves (occurs at oval window)
- Fluid waves → movement of hair cells which opens ion channels
- Movement of hair cells → action potential
The cochlear nerve transmits action potentials from the primary auditory neurons to the cochlear neurons in which brain structure on their way to the auditory cortex?
The medulla
How do non-neural hair cells generate action potentials in the primary sensory neurons?
By bending back and forth, causing ion channels to open and close
What is the neural pathway of audition? (seven steps)
- Hair receptor cells
- Primary neurons
- Secondary neurons
- Tertiary neurons
- Quaternary neurons
- Primary auditory cortex
- Connections to other areas
Where are the primary neurons involved in audition located?
The auditory nerve
Where are the secondary neurons involved in audition located?
The superior olivary nucleus
Where are the tertiary neurons involved in audition located?
The inferior colliculus
Where are the quaternary neurons involved in audition located?
The medial geniculate nucleus of the thalamus
In which lobe is the primary auditory cortex located?
The superior temporal lobe
What are the two types of photoreceptors?
- Rods
- Cones
What type of photopigment is found within rods?
Rodopsin
Are there more rods or cones in the visual system?
Rods
Are rods activated by intense or low levels of light?
Low levels
Do rods or cones allow for night vision?
Rods
What term is used to describe the rapid depletion of rods in bright light?
Photobleaching
Are rods more densely packed in the fovea or spread throughout the periphery?
Spread throughout the periphery
What type of photopigment is found within cones?
Photopsin
Are cones activated by intense or low levels of light?
Intense
Do rods or cones allow for colour vision?
Cones
Are cones more densely packed in the fovea or spread throughout the periphery?
Densely packed in the fovea
Where is human’s visual acuity the best?
The centre of the visual field (the fovea)
The ability of the lens to bend light to focus it on the retina is known as what?
Accommodation
Do relaxed ciliary muscles cause ligaments to stretch or loosen?
Stretch
How do the ciliary muscles alter the lens to allow the eye to see objects that are far away?
Flattens the lens to let more light in
Do contracted ciliary muscles cause ligaments to stretch or loosen
Loosen
How do the ciliary muscles alter the lens to allow the eye to see objects that are close up?
Rounds the lens to focus light
What region of the eye does not contain any rods or cones and is often referred to as the blind spot?
The optic disk
What role does the pigment epithelium play in vision?
Absorbs extra light and prevents that light from reflecting back and distorting vision
In the absence of light, is NT release onto bipolar neurons tonic or phasic?
Tonic
T or F: In the presence of light, NT release increases in proportion to the amount of light.
False. Decreases in proportion to the amount of light.
T or F: Multiple photoreceptors converge on one ganglion cell.
True
T or F: Bipolar cells are activated by light, regardless of their type.
False. Bipolar cells are either activated or inhibited by light, depending on their type.
When do ganglion cells respond the strongest?
When there is good contrast of light intensity between the centre1 and the surround
What is the neural pathway of vision?
- Rods and cones
- Bipolar cells (primary neurons)
- Ganglion cells (secondary neurons)
- Axons in the optic nerve
- Thalamus and superior colliculus
- Secondary visual areas and extrastriate visual areas
- Connections to other areas
What is the optic chiasm?
Where the ipsilateral optic nerve of each eye crosses over into the contralateral hemisphere
T or F: Each eye has both ipsilateral and contralateral pathways.
True
When do simple cortical cells respond maximally?
When input is in the orientation of their receptive field
Are things that form patterns that are familiar/ meaningful more or less likely to become grouped together when being perceived?
More likely
When perceiving faces, where does initial processing occur?
The occipital cortex
When perceiving faces, what occurs in the fusiform gyrus?
Identification
Which brain structure responds only to faces (or to stimuli that resemble faces)?
The fusiform face area
When perceiving faces, what does the superior temporal sulcus respond to?
Where a person is looking and their mouth movements
Which brain region is activated when evaluating facial attractiveness?
The frontal cortex
A disruption in the infrotemporal pathway from the temporal lobe to the amygdala is thought to cause which disorder?
Capgras
According to the McGurk effect, when listening to a recording of “fa”/”ba” but watching a video of someone mouthing the opposite, do people perceive the sound based on what they are hearing or what they are seeing?
What they are seeing
The inferior prefrontal cortex, premotor cortex, posterior parietal cortex, and posterior superior temporal sulcus all showed an increased BOLD response to what type of stimulation?
Multisensory stimulation
Can perceptual processing change/reorganize overtime?
Yes
T or F: Changes in perceptual processing always occur gradually.
False. Can be gradual or sudden.
