bio psych chap. 9

Adequate Stimulus

specific type of energy or event that a particular sensory receptor is most sensitive to and responds to

EX: light

Agraphia

the inability to write, due to brain damage

Alexia

the inability to read, due to brain damage

Amplitude

the physical energy in a sound, the sound’s intensity

Angular Gyrus

a gyrus at the border of the parietal and occipital lobes containing pathways that connect the visual area with auditory, visual, and somatosensory association area in the temporal and parietal lobes. Damage results in alexia and agraphia

Aphasia

language impairment caused by damage to the brain

Auditory Object

a sound that we recognize as having an identity that is distinct from other sounds

Basilar Membrane

the membrane in the cochlea that separates the cochlear canal from the tympanic canal, and on which the organ of Corti is located

Binaural

involving the use of both ears

Brocas’s Aphasia

Language impairment caused by damage to Broca’s Area and surrounding cortical and subcortical areas

Cochlea

the snail shaped structure where the ear’s sound analyzing structures are located

Cochlear Canal

the middle canal in the cochlea; contains the organ of Corti

Cocktail Party Effect

the ability to sort out meaningful auditory messages from a complex background of sounds

Coincidence Detectors

Neurons that fire most when they receive input from both ears at the same time; involved in sound localization

Complex Sound

a sound composed of more than one pure tone

Dialect

difference in subtle aspects of a language within a population due to regional or cultural isolation from other speakers, resulting in different words for the same concept that are stable across generations. For example, calling a carbonated beverage either “pop“ or “soda“, or saying either “you all‘ or “y’all“

Dyslexia

an impairment of reading, which can be developmental or acquired through brain damage

Eustachian Tube

the connection between the middle ear and the oral cavity, the function of which is to equalize air pressure differences between the outside of the head and the middle ear

Frequency

a characteristic of sound; the number of cycles or waves of alternating compression and decompression of the vibrating medium that occur in a second. For the psychological perception of frequency, see pitch

Frequency-Place Theory

the hypothesis that frequency following individual neurons accounts for the discrimination of frequencies up to about 200 Hz, and higher frequencies are represented by the place of greatest activity on the basilar membrane

Frequency Theory

any one of several hypotheses of auditory frequency analysis that state that the frequency of a sound is represented in the firing rate of each neuron or a group of neurons

Inner Hair Cells

a single row of about 3500 hair cells located on the basilar membrane toward the inside of the cochlea’s coil; they produce most, if not all, of the auditory signal

Intensity

the physical energy in a sound; the sound’s amplitude. For the psychological perception of intensity, see loudness

Interaural Intensity Difference (IID)

a binaural cue to the location of a sound coming from one side that results from the sound shadow created by the head; most effective above 2000 to 3000 Hz

Interaural Phase Difference (IPD)

a binaural cue to the location of a sound coming from one side due to the difference in the phase of the sound wave between the two ears

Interaural Timing Difference (ITD)

a binaural cue to the location of a sound coming from one side due to the time the sound requires to travel the distance between the ears; most effective for low-frequency sounds

Language Acquisition Device

A part of the brain hypothesized to be dedicated to learning and controlling language

Organ of Corti

the sound analyzing structure on the basilar membrane of the cochlea; it consists of four rows of hair cells, their supporting cells, and the tectorial membrane

Ossicles

tiny bones in the middle ear that operate in lever fashion to transfer vibration from the membrane to the cochlea; they also produce a slight amplification of the sound

Outer Hair Cells

three rows of about 12000 cells located on the basilar membrane toward the outside of the cochlea’s coil; they amplify the cochlea’s output and sharpen frequency tuning, possibly by adjusting the tension of the tectorial membrane

Perception

the interpretation of sensory information

Phonological Hypothesis

the idea that the fundamental problem in dyslexia is impaired phoneme processing

Pinna

the ear flap on each side of the head; the outer ear

Pitch

the experience of the frequency of a sound

Place Theory

a theory that states that the frequency of a sound is identified by the location of maximal vibration on the basilar membrane and which neurons are firing most

Planum Temporale

the area in each temporal lobe that is the location in the left hemisphere of Wrenicke’s Area and that is larger on the left in most people

Prosody

the use of intonation, emphasis, and rhythm to convey meaning in speech

Pure Tone

a sound consisting of a single frequency

Receptor

a cell, often a specialized neuron, that is suited by its structure and function to respond to a particular form of energy, such as sound

Sensation

the acquisition of sensory information

Tectorial Membrane

a shelf like membrane overlying the hair cells and basilar membrane in the cochlea

Telephone Theory

a theory of auditory frequency analysis, which stated that the auditory neurons transmit the actual sound frequencies to the cortex

Tonotopically Organized

neurons from adjacent receptor locations project to adjacent cells in the auditory cortex, forming a tonotopic map

Tympanic Membrane

the eardrum, a very thin membrane stretched across the end of the auditory canal; its vibration transmits sound energy to the ossicles

Volley Theory

hypothesis of auditory frequency analysis that states that groups of neurons follow the frequency of a sound when the frequency exceeds the firing rate capability of a single neuron

Wernicke’s Aphasia

language impairment resulting from damage to Wernicke’s Area'; the person has difficulty understanding and producing spoken and written language