Post Midterm 2 Psyc 212

Phonemes

Unit of sound that forms the basis of speech and distinguishes one word from another in particular language

What is the IPA used for?

Differentiating sound and written word

Respiration

When air is pushed out of the lungs through trachea and up to larynx

Phonation

Vocal chords vibrate in response to air being pushed through them

More tension in vocal chords causes

Higher pitched voices, as do smaller vocal folds

Articulation

Process of producing speech via vocal tract and changes based on changes to jaw, lips, tongue

Formats

Resonant frequencies, peaks in speech spectrum

Three dimensions of spectrograms

Time, frequency, energy

Coarticulation

The overlap of articulatory or speech patterns, comes from experienced speakers positioning tongue before next vowels/constant

McGurk Effect

Resolves problem of coarticulation through vision, shows that we are affected by what we see

Motor theory of speech perception

Use reverse process of speech to understand what people are saying to us. We know how to speak and thus can infer what someone else is saying

Problem that arises from McGurk effect

speech production and vision perception is complex, so its limited

Solution to McGurk effect problem

Reduce the number of phonetic categories

Learning to Listen

Babies learn to distinguish particular acoustics early on before they start producing their own speech

What is a possible reason for the reduction in audible phonemes?

Forced categorization that may help us differentiate two sounds as different

Wernickes area

Responsible for associating sound patterns with meaning

Pathway for wenickes area

Primary auditoru cortex, Wernick, Broca, primary motor cortex

Brocas aphasia

Leads to difficulty in finding right articulation of words, able to understand what is being said to them

Wernickes aphasia

Production of coherent speech, inability to understand or assign meaning to sounds

Tone height and chroma

Height refers to level of pitch (related to frequency), chroma refers to shared qualities by tones that share an octave

Octave

Ration of 2:1, interval between 2 sound frequencies

What are semitones

12 equally spaced pitch intervals

Consonance

Pleasing combos of 2+ notes that arise from simple rations of fundamental frequencies

Dissonance

Unpleasant combos of 2+ notes that arise from complex rations of F.F, few coinciding harmonies

Scale

Particular subset of notes in a given octave

Key

Scale that functions as basis of musical composition

Tonic

Root notes of a key which acts as the gravity point of that key

What makes music pleasing?

Moving to and from root key

Where is music mostly processed in the brain?

Right auditory cortex and parabelt region

Melodic contour?

patterns tha rises and drops in pitch, defines melody regardless of the notes

Congenital amusia

Umbrella term for music deficiencies that arise not as a lack of intellectual ability, brain damage after brith or lack of exposure

Symptoms of amusia

Inability to distinguish small differences in pitch, tones that are out of key

ERAN and P600

Negative event related potentials occurring 200ms after melodic tonal violation. vs positive ERP that occur after 600ms

AMusics dont have P600 which suggests?

Lack conscious access to processed pitch deviances

Absolute Pitch

Rare ability where some people can very accurately name or produce notes without comparison to other notes

Proprioception and case study

Perception of body in space, based on ability to perceive the position of joints, includes verstibular sensations

Kinesthesia

Perception of movement w the exclusion of balance, uses the same receptors as proprioception

Muscle spindle

Kinesthetic nerve fibers attached to muscular fibers, perceives the stretching of muscles from within

Golgi tendon organ

in tendons, part of the muscle attached to articulation, able to perceive amount of pull in tendon

Tactile perception

Perception of objects that come into contact with the skin

Exteroceptive sense

perception of external world, associated with peripheral nerve fibers

Thermalgesia

Temperature and pain, uses interoceptive sense which is the perception of the internal state of the body

Somesthetic nerve fibers

difference in nerve fiber myelination between touch and proprioception versus pain fibers

Tactile perception

4 types, classified by receptive fields and rate of adaptation,

Slow adaptation rates will..

start firing when contacted with stimulus, and continue to fire as long as contact is maintained

Fast adaption will…

start firing as with contact to stimulus, stop firing if contact is maintained

SA1 Cells —> Merkel

Small receptive field with slow adaptation, good for fine grain patterns of tactile stimulation

SA2 cells —> Ruffini

Large receptive fields, slow adaptation, good for position of hands via skin

FA1 Fibers: Meissner

Large receptive fields, fast adaptation, good for maintain grip on objects

FA2 Fibers: Pacini

Fast adaptation rate, small receptive fields, good for interaction with tools

Example pathway of a key

• Sa1 to feel the key → Sa2 to grasp key → Fa1 to maintain grip on key while unlocking door → Fa2 to feel when key has hit the end of the lock chamber

End sequence of touch fibers

converge to form nerve that enters the spinal cord between each spinal disc, patch of skin innervated by specific nerve called dermatome

Dosal column pathway

backside of spine, remains on the same side then crosses over onto 2 different nuclei, then to thalamus

types of nuclei

gracile and cuneate nucleus

Two point discrimination threshold

Perception of distance between two pins, higher number means larger distance between two pins to perceive pints as two distinct objects

Pain

an unpleasant sensory and emotional experience associated with or resembling association with an actual or potential tissue damage

Nociception

neural process of encoding nociceptive stimuli

Nociceptive stimulus

an actual or potentially tissue damaging event transduced and encoded by nociceptors

Two groups of peripheral nociceptors

A delta fibers and C fibers

A delta fibers

intermediate sized myelinated sensory nerve fibers that transmit pain and temperature signals

C fibers

small diameter non myelinated sensory nerve fibers that transmit pain and temperature signals

two stages that pain occurs in

sharp rapid pain followed by throbbing sensation

Throbbing sensation is mediate by…

c fibers

sharp rapid pain mediate by…

a delta fibers

how does local anesthetics work?

prevents sodium from entering sodium channel, this is how action potential propagates so no AP

Saltatory conduction

leads to jumping of AP from nodes of ranvier, thus 3 NoR rule to block AP in myelinated axons

Congenital insensitivity to pain

Prone to injury due to lack of nociceptive receptors

Limbic touch

Unmyelinated tactile afferents signal tough and project to insular cortex

For limbic touch, define both receptor types

Tactile receptors for sensation itself and receptors that encode pleasantness

Taste

perception of taste stimuli via interaction between soluble substances with gustatory receptors located in taste buds of the tongue

Smell

perception of smell using receptors located in olfactory mucosa in upper portion of nasal cavity

Trigeminal system

Chemesthesis is third chemosensory system next to smell and taste, receptors are located on fibers of the trigeminal nerve of the nasal and oral mucosa

What do trigeminal stimuli envoke?

irritation, burning or freshness

Taste buds located on

mucosa and papillae

Filiform papillae

somatosensory perception of the tongue, nothing to do with taste, texture of food

central pathway

tongue via cranial nerves to brainstem, to thalamus, insular and parietal cortex

2 anterior thirds are connect to brain via..

cranial nerve 7

posterior one third of tongue connected to brain via

cranial nerve 9

other taste buds found on epiglottis connected to brain via

cranial nerve 10

where do all cranial nerves connect to?

solitary nucleus of brainstem and then to the thalamus

Upper portion of nasal cavity contains

olfactory mucosa, sensory cells that are exposed to outside

Olfactory receptor neurons

Situated in roof portion of the nasal cavity, surrounded by supporting cells that regenerate stem cells

Olfactory code

humans have about 400 different types of olfactory receptors

specifications of olfactory receptor types

each ORN carry 1 receptor type, can be activated by different substances

Variation in human population

infinte types of combos for receptor types in each person, we all experience different smells

Where do all axons of the ORN pass through?

Cribiform plate of the ethmoid bone to reach the olfactory bulb

Olfactory bulb

where first synapses take place

Axons of olfactory neurons converge on one ….

glomerulus and do not cross over (occurs epsilaterally to brain)

Parts of olfactory processing areas that are part of the limbic system

amygdala, entorhinal, orbitofrontal cortex

Implications of direction to brain

memory and scene are intertwined, do not go through thalamus, create more vibrant memories triggered by scent

Orthonasal olfaction

volatile substances are released from the odor source and reach olfactory cleft within the respiration air stream

Retronasal smelling

substances reach odor source during swallowing

Smell functions

warning, nutrition, social communication

Anosmia

complete loss of olfactory function

Hyposmia

parietal loss of olfactory function

Parosmia

odors are perceived differently than they are supposed to

Phantosmia

perception of smells in the absence of an odor

Parkinsons and alzheimers

olfactory dysfunction predate diagnosis by 10-15 years

Factors that influence olfaction

age, sex, education level, bmi and blood preassure