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NHPC BASLP practice questions

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Question 1Anatomy and Physiology of the Auditory and Speech Systems

Which ossicle is directly attached to the tympanic membrane on its lateral surface?

  1. Stapes
  2. Incus
  3. Stapedius
  4. Malleus Correct answer.

Explanation

The handle (manubrium) of the malleus is embedded in the fibrous layer of the tympanic membrane, so the malleus is the ossicle directly coupled to the eardrum. The chain then continues medialward through the incus to the stapes.

Question 2Anatomy and Physiology of the Auditory and Speech Systems

The receptor hair cells of the cochlea are located within which structure?

  1. The spiral ganglion
  2. The organ of Corti Correct answer.
  3. The stria vascularis
  4. Reissner's membrane

Explanation

The organ of Corti rests on the basilar membrane and contains the inner and outer hair cells together with their supporting cells. Mechanoelectrical transduction of basilar membrane motion occurs there.

Question 3Anatomy and Physiology of the Auditory and Speech Systems

A lesion of the recurrent laryngeal nerve most directly impairs which function?

  1. Abduction of the vocal folds Correct answer.
  2. Elevation of the soft palate
  3. Tensing of the vocal folds
  4. Closure of the vocal folds

Explanation

The recurrent laryngeal nerve supplies all intrinsic laryngeal muscles except the cricothyroid, including the posterior cricoarytenoid, the sole abductor of the vocal folds. Its damage therefore impairs abduction and predisposes to airway compromise.

Question 4Anatomy and Physiology of the Auditory and Speech Systems

Which muscle is the primary abductor of the vocal folds?

  1. Posterior cricoarytenoid Correct answer.
  2. Thyroarytenoid
  3. Lateral cricoarytenoid
  4. Cricothyroid

Explanation

The posterior cricoarytenoid rotates the arytenoid cartilages laterally, moving the vocal processes apart and widening the glottis. It is the only intrinsic muscle that abducts the folds.

Question 5Anatomy and Physiology of the Auditory and Speech Systems

The endocochlear potential of approximately +80 mV is generated mainly by which structure?

  1. The tectorial membrane
  2. The stria vascularis Correct answer.
  3. The basilar membrane
  4. The spiral ligament

Explanation

The stria vascularis actively secretes potassium into scala media, producing a high-potassium, positive-potential endolymph. This electrochemical gradient drives potassium influx through hair cell stereocilia during transduction.

Question 6Anatomy and Physiology of the Auditory and Speech Systems

Tonotopic organisation along the basilar membrane means that high-frequency sounds maximally displace which region?

  1. The middle turn only
  2. The apex, near the helicotrema
  3. The base, near the oval window Correct answer.
  4. The hook region of the spiral ganglion

Explanation

The basilar membrane is narrow and stiff at the base and wide and flaccid at the apex, so high frequencies peak basally and low frequencies apically. This place coding underpins pitch perception.

Question 7Anatomy and Physiology of the Auditory and Speech Systems

A pure-tone audiogram shows normal thresholds by air conduction but an air-bone gap of 30 dB. This pattern is most consistent with which finding?

  1. Normal hearing
  2. Conductive loss Correct answer.
  3. Retrocochlear pathology
  4. Sensorineural loss

Explanation

An air-bone gap indicates that bone conduction is better than air conduction, meaning the outer or middle ear impedes sound transmission. This is the hallmark of conductive hearing loss.

Question 8Anatomy and Physiology of the Auditory and Speech Systems

The acoustic reflex is elicited by loud sound and produces contraction of which muscle?

  1. Tensor tympani only
  2. Cricothyroid
  3. Stapedius Correct answer.
  4. Levator veli palatini

Explanation

The stapedius muscle contracts in response to intense sound, stiffening the ossicular chain and reducing low-frequency transmission. Its motor supply is the facial nerve, which explains absent reflexes in facial palsy.

Question 9Anatomy and Physiology of the Auditory and Speech Systems

Which cranial nerve carries the efferent limb of the acoustic reflex?

  1. Facial Correct answer.
  2. Trigeminal
  3. Glossopharyngeal
  4. Vagus

Explanation

The stapedius is innervated by the facial nerve, so the efferent arc of the acoustic reflex travels via CN VII. This is why the reflex is abolished in ipsilateral facial nerve lesions.

Question 10Anatomy and Physiology of the Auditory and Speech Systems

The primary auditory cortex is located in which region?

  1. Postcentral gyrus
  2. Cingulate gyrus
  3. Superior temporal gyrus Correct answer.
  4. Precentral gyrus

Explanation

Heschl's gyrus on the superior surface of the superior temporal gyrus houses the primary auditory cortex, corresponding to Brodmann areas 41 and 42. It receives tonotopically organised input from the medial geniculate body.

Question 11Anatomy and Physiology of the Auditory and Speech Systems

Which structure is the first central relay in the auditory pathway?

  1. Superior olivary complex
  2. Inferior colliculus
  3. Medial geniculate body
  4. Cochlear nucleus Correct answer.

Explanation

Auditory nerve fibres terminate in the cochlear nuclei of the medulla, which are the first synaptic relay after the spiral ganglion. Processing then proceeds to the superior olive, inferior colliculus and medial geniculate body.

Question 12Anatomy and Physiology of the Auditory and Speech Systems

Binaural processing for localising sound in the horizontal plane first occurs at which level?

  1. Medial geniculate body
  2. Inferior colliculus
  3. Cochlear nucleus
  4. Superior olivary complex Correct answer.

Explanation

The superior olivary complex receives input from both ears and compares interaural time and intensity differences. This makes it the earliest site of binaural convergence for horizontal localisation.

Question 13Anatomy and Physiology of the Auditory and Speech Systems

The vowel /i/ differs acoustically from /a/ mainly because /i/ has which characteristic?

  1. Identical formants with greater intensity
  2. A lower first formant and lower second formant
  3. A higher first formant and higher second formant
  4. A lower first formant and higher second formant Correct answer.

Explanation

Vowels are distinguished by formant frequencies reflecting tongue height and advancement. The high front vowel /i/ has a low F1 and a high F2, whereas /a/ has a high F1 and a relatively low F2.

Question 14Anatomy and Physiology of the Auditory and Speech Systems

The source-filter theory of speech production states that the vocal tract primarily acts as which of the following?

  1. A generator of the fundamental frequency
  2. A resonator that filters the glottal source Correct answer.
  3. A detector of auditory feedback
  4. A generator of the subglottal pressure

Explanation

In the source-filter model, the vibrating vocal folds generate a harmonic source and the vocal tract filters it, shaping spectral peaks into formants. Fundamental frequency is set by the source, not the filter.

Question 15Anatomy and Physiology of the Auditory and Speech Systems

Which cranial nerve supplies most of the muscles of the tongue?

  1. Facial
  2. Glossopharyngeal
  3. Hypoglossal Correct answer.
  4. Trigeminal

Explanation

The hypoglossal nerve supplies all intrinsic and most extrinsic tongue muscles, with palatoglossus being the exception. Tongue movement for articulation therefore depends chiefly on CN XII.

Question 16Anatomy and Physiology of the Auditory and Speech Systems

During production of a voiced stop, which sequence correctly describes the articulatory events?

  1. Continuous airflow with no closure
  2. Closure, build-up of intraoral pressure, release, then voicing onset Correct answer.
  3. Closure, release, then sustained voicing
  4. Voicing throughout with no pressure build-up

Explanation

A voiced stop involves a complete articulatory closure during which intraoral pressure rises, followed by a release burst and then onset of voicing. The timing between release and voicing onset defines voice onset time.

Question 17Anatomy and Physiology of the Auditory and Speech Systems

The Bernoulli effect contributes to vocal fold vibration by explaining which phenomenon?

  1. Increased subglottal pressure during exhalation
  2. Suction that draws the folds together as air flows between them Correct answer.
  3. Closure of the ventricular folds
  4. Lengthening of the vocal folds during phonation

Explanation

As air passes through a narrowed glottis, its velocity increases and pressure between the folds drops, drawing them toward midline. Combined with tissue elasticity, this supports the mucosal wave of phonation.

Question 18Anatomy and Physiology of the Auditory and Speech Systems

Which structure separates the scala media from the scala vestibuli?

  1. Tectorial membrane
  2. Osseous spiral lamina
  3. Reissner's membrane Correct answer.
  4. Basilar membrane

Explanation

Reissner's (vestibular) membrane forms the roof of the cochlear duct and separates scala media from scala vestibuli. The basilar membrane forms its floor, separating scala media from scala tympani.

Question 19Anatomy and Physiology of the Auditory and Speech Systems

Damage to the left auditory cortex after the level of the cochlear nuclei typically produces what pattern?

  1. Loss confined to the ipsilateral ear only
  2. Equal loss in both ears
  3. Complete deafness in both ears
  4. Greater threshold loss in the contralateral ear Correct answer.

Explanation

Ascending auditory fibres cross extensively, but the crossed projection predominates, so cortical lesions affect the contralateral ear more. Because of bilateral representation, unilateral lesions rarely cause profound deafness.

Question 20Anatomy and Physiology of the Auditory and Speech Systems

The tensor tympani muscle is innervated by which nerve?

  1. Hypoglossal
  2. Trigeminal Correct answer.
  3. Glossopharyngeal
  4. Facial

Explanation

The tensor tympani is supplied by a branch of the mandibular division of the trigeminal nerve. It tenses the tympanic membrane and is distinct from the stapedius, which the facial nerve supplies.

Question 21Anatomy and Physiology of the Auditory and Speech Systems

Which type of hearing loss is typically associated with recruitment?

  1. Mixed loss
  2. Cochlear sensorineural loss Correct answer.
  3. Retrocochlear loss
  4. Conductive loss

Explanation

Recruitment reflects abnormal loudness growth from damaged outer hair cells in the cochlea, so sounds above threshold are perceived as disproportionately loud. It is characteristic of cochlear lesions rather than conductive or retrocochlear ones.

Question 22Anatomy and Physiology of the Auditory and Speech Systems

A patient speaks with hypernasality. This most directly indicates dysfunction of which mechanism?

  1. Vocal fold adduction
  2. Tongue elevation
  3. Diaphragmatic support
  4. Velopharyngeal closure Correct answer.

Explanation

Hypernasality arises when the velopharyngeal port fails to close, allowing nasal resonance during oral sounds. It points to palatal or pharyngeal dysfunction rather than laryngeal or respiratory problems.

Question 23Anatomy and Physiology of the Auditory and Speech Systems

Which muscle lengthens and tenses the vocal folds, thereby raising pitch?

  1. Thyroarytenoid
  2. Posterior cricoarytenoid
  3. Vocalis
  4. Cricothyroid Correct answer.

Explanation

The cricothyroid approximates the thyroid and cricoid cartilages, elongating the vocal folds and increasing tension, which raises fundamental frequency. It is the only intrinsic muscle supplied by the superior laryngeal nerve.

Question 24Anatomy and Physiology of the Auditory and Speech Systems

The middle ear transformer mechanism improves transmission of sound from air to cochlear fluid mainly by which means?

  1. Eliminating the impedance mismatch entirely
  2. Amplifying sound by active muscle contraction
  3. Increasing the area of the tympanic membrane relative to the stapes footplate alone
  4. Reducing the effective area and increasing force at the oval window Correct answer.

Explanation

The large tympanic membrane collects force over a broad area, and the ossicular lever concentrates it onto the much smaller stapes footplate. The resulting pressure gain largely overcomes the air-to-fluid impedance mismatch.

Question 25Neurology and Neurophysiology of Communication

Which cortical region is classically described as Broca's area, the motor speech centre for articulate language output?

  1. Anterior cingulate gyrus on the medial surface of the frontal lobe
  2. Posterior third of the superior temporal gyrus of the dominant hemisphere
  3. Inferior frontal gyrus (pars opercularis and triangularis) of the dominant hemisphere Correct answer.
  4. Supramarginal gyrus at the posterior end of the lateral sulcus

Explanation

Broca's area occupies the posterior part of the inferior frontal gyrus, chiefly the pars opercularis and pars triangularis, in the language-dominant hemisphere. Damage here produces non-fluent aphasia with relatively preserved comprehension. The region lies just anterior to the lower motor cortex controlling the articulators.

Question 26Neurology and Neurophysiology of Communication

A lesion of the left arcuate fasciculus typically produces which aphasia profile?

  1. Severe comprehension loss with echolalia and no spontaneous speech
  2. Non-fluent speech with good comprehension and intact repetition
  3. Fluent speech with poor comprehension and no repetition deficit
  4. Fluent speech with good comprehension but markedly impaired repetition Correct answer.

Explanation

The arcuate fasciculus connects Wernicke's to Broca's area, so its disruption yields conduction aphasia: fluent output, preserved comprehension, but disproportionate difficulty repeating. The repetition failure reflects a disconnection between auditory comprehension and motor speech programming. Naming is usually impaired as well.

Question 27Neurology and Neurophysiology of Communication

In a lower motor neuron lesion of the facial nerve, which pattern of weakness is expected?

  1. Bilateral weakness confined to the orbicularis oris
  2. Weakness of the ipsilateral upper and lower face Correct answer.
  3. Weakness of the contralateral upper and lower face
  4. Weakness of the contralateral lower face only

Explanation

The facial nerve supplies both upper and lower facial muscles on the same side, so a lower motor neuron lesion paralyses the entire ipsilateral hemiface, including forehead wrinkling and eye closure. Upper motor neuron lesions spare the forehead because the upper face receives bilateral corticobulbar input. This distinction is central to bedside localisation.

Question 28Neurology and Neurophysiology of Communication

Spastic dysarthria following bilateral upper motor neuron disease is best characterised by which cluster of speech features?

  1. Irregular articulatory breakdowns with fluctuating hypernasality
  2. Monotone voice with normal rate and normal articulation
  3. Rapid bursts of speech with distorted vowels and irregular rhythm
  4. Strained-strangled voice with slow rate and imprecise consonants Correct answer.

Explanation

Spastic dysarthria reflects bilateral corticobulbar damage, producing hypertonia and reduced range of movement. Listeners hear strained-strangled phonation, slow rate, imprecise consonants and harsh voice quality. Pseudobulbar affect and exaggerated gag may accompany it.

Question 29Neurology and Neurophysiology of Communication

Which structure forms the main descending pathway carrying cortical motor commands for skilled voluntary movement to the spinal cord?

  1. Ventral spinocerebellar tract
  2. Dorsal column-medial lemniscus pathway
  3. Lateral corticospinal tract Correct answer.
  4. Spinothalamic tract

Explanation

The corticospinal tract originates in motor cortex, decussates in the medullary pyramids and descends in the lateral funiculus to synapse on anterior horn cells. It mediates fine, fractionated voluntary movement. The other listed tracts are ascending sensory pathways.

Question 30Neurology and Neurophysiology of Communication

Damage to the left primary auditory cortex in Heschl's gyrus most typically results in which finding?

  1. Impaired localisation and processing of complex sounds, with hearing largely preserved Correct answer.
  2. Total loss of speech comprehension with normal pure-tone thresholds
  3. Selective loss of low-frequency hearing in both ears
  4. Complete bilateral deafness

Explanation

Auditory input is bilaterally represented, so unilateral cortical damage rarely causes deafness. Instead it impairs sound localisation, temporal processing and discrimination of complex or competing signals. Comprehension of speech may be affected only under demanding conditions.

Question 31Neurology and Neurophysiology of Communication

The primary role of the cerebellum in speech motor control is best described as which of the following?

  1. Initiating voluntary speech through direct cortical excitation
  2. Storing the semantic representations of words
  3. Coordinating timing, force and accuracy of ongoing articulatory movements Correct answer.
  4. Generating the emotional prosody of utterances

Explanation

The cerebellum compares intended with actual motor output and adjusts timing, amplitude and coordination of movement, including speech. Its damage produces ataxic dysarthria with irregular breakdowns and overshooting. It does not generate language content or emotional prosody.

Question 32Neurology and Neurophysiology of Communication

A patient shows intact comprehension, fluent speech and normal repetition but cannot name objects, with errors that improve when given a phonemic cue. Which aphasia is most likely?

  1. Conduction aphasia
  2. Anomic aphasia Correct answer.
  3. Wernicke's aphasia
  4. Broca's aphasia

Explanation

Anomic aphasia is defined by disproportionate naming difficulty with otherwise fluent, well-comprehended speech and preserved repetition. Phonemic cueing often yields the target word, indicating a retrieval rather than storage failure. Other language domains remain relatively intact.

Question 33Neurology and Neurophysiology of Communication

In Parkinson's disease, hypokinetic dysarthria most characteristically shows which feature?

  1. Markedly increased loudness with slow, deliberate rate
  2. Strained voice with prolonged phonation
  3. Reduced loudness with rapid rushes of short phrases Correct answer.
  4. Irregular hypernasality with scanning speech

Explanation

Hypokinetic dysarthria reflects basal ganglia dysfunction with rigidity and reduced amplitude. Speech shows hypophonia, monotone pitch, imprecise consonants and short rushes of rapid speech. The pattern differs from the strained quality of spastic dysarthria.

Question 34Neurology and Neurophysiology of Communication

Which cranial nerve provides motor innervation to the intrinsic muscles of the tongue?

  1. Glossopharyngeal nerve (IX)
  2. Trigeminal nerve (V)
  3. Facial nerve (VII)
  4. Hypoglossal nerve (XII) Correct answer.

Explanation

The hypoglossal nerve supplies all intrinsic and most extrinsic tongue muscles, controlling shape and position for articulation and swallowing. A lesion causes ipsilateral wasting and deviation toward the weak side on protrusion. Other nerves listed serve sensation, facial expression or pharyngeal function.

Question 35Neurology and Neurophysiology of Communication

A left middle cerebral artery infarct involving the superior temporal and inferior parietal cortex would most likely produce which combination?

  1. Fluent paraphasic speech with poor comprehension and impaired repetition Correct answer.
  2. Severe dysarthria with intact written language
  3. Non-fluent effortful speech with good comprehension and spared repetition
  4. Normal spontaneous speech with isolated word-finding pauses

Explanation

The posterior superior temporal region houses Wernicke's area, so infarction there yields fluent but paraphasic speech, poor auditory comprehension and impaired repetition. Written language and reading are usually affected in parallel. This is the classic posterior superior division syndrome.

Question 36Neurology and Neurophysiology of Communication

The basal ganglia contribute to speech motor control mainly by which mechanism?

  1. Regulating the initiation, scaling and gating of movement through thalamocortical loops Correct answer.
  2. Encoding phoneme categories in the auditory association cortex
  3. Directly exciting lower motor neurons in the brainstem
  4. Generating the respiratory rhythm used for speech

Explanation

The basal ganglia modulate cortical motor output through direct, indirect and hyperdirect pathways relaying via the thalamus. This regulates movement initiation, amplitude scaling and suppression of unwanted movement, including speech. Loss of dopamine produces hypokinesia and hypophonia.

Question 37Neurology and Neurophysiology of Communication

Brodmann area 44 and 45 together constitute which functional region?

  1. Primary motor cortex
  2. Wernicke's area
  3. Primary somatosensory cortex
  4. Broca's area Correct answer.

Explanation

Areas 44 and 45 correspond to the pars opercularis and pars triangularis of the inferior frontal gyrus, collectively Broca's area. They support speech production, syntax and articulatory planning. Area 4 is primary motor and area 22 is Wernicke's.

Question 38Neurology and Neurophysiology of Communication

A patient with right-hemisphere stroke shows flat, monotone speech, poor use of gesture and failure to grasp jokes, while grammar and repetition are intact. Which domain is primarily affected?

  1. Pragmatic and prosodic communication Correct answer.
  2. Phonological processing
  3. Syntactic parsing
  4. Articulatory planning

Explanation

The right hemisphere supports prosody, pragmatics, inference and discourse organisation. Damage produces aprosodia, literal interpretation and poor turn-taking while core phonology and syntax remain intact. This profile contrasts with left-hemisphere aphasia.

Question 39Neurology and Neurophysiology of Communication

Which statement best explains why bilateral rather than unilateral corticobulbar damage is required for persistent spastic dysarthria?

  1. Corticobulbar fibres decussate twice before reaching the nuclei
  2. The cranial nerve nuclei are located entirely in the midbrain
  3. Each side of the brainstem receives crossed and uncrossed corticobulbar fibres, so unilateral loss is compensated Correct answer.
  4. Speech muscles are innervated only by the hypoglossal nerve

Explanation

Most cranial nerve motor nuclei, especially those for the upper face, jaw, tongue and larynx, receive both crossed and uncrossed corticobulbar input. A unilateral lesion is therefore substantially compensated, whereas bilateral disease produces the hypertonia and slow movement of spastic dysarthria. This is why pseudobulbar palsy follows bilateral lesions.

Question 40Neurology and Neurophysiology of Communication

In ataxic dysarthria from cerebellar disease, which perceptual feature is most characteristic?

  1. Audible inspiratory stridor throughout speech
  2. Irregular articulatory breakdowns with overshooting and variable rate Correct answer.
  3. Monotone pitch with reduced loudness
  4. Consistently hypernasal resonance with nasal emission

Explanation

Cerebellar damage disrupts timing and force calibration, so speech shows irregular breakdowns, excess and uneven stress, and variable rate. The term scanning speech describes this alternating pattern. Hypernasality and monotone pitch belong to other dysarthria types.

Question 41Acoustics, Psychoacoustics, and Speech Science

A pure tone has a frequency of 1000 Hz. What is its period?

  1. 10 ms
  2. 100 ms
  3. 0.1 ms
  4. 1 ms Correct answer.

Explanation

Period is the reciprocal of frequency, so T = 1/f = 1/1000 s = 0.001 s, which equals 1 ms. This relationship holds for any sinusoidal signal and is fundamental to describing temporal features of sound.

Question 42Acoustics, Psychoacoustics, and Speech Science

On the conventional audiometric (dB HL) scale, 0 dB HL at 1000 Hz represents which reference?

  1. The average threshold of audibility for young normal-hearing adults Correct answer.
  2. The maximum comfortable loudness level
  3. The physical intensity of 0 dB SPL
  4. The threshold of pain for normal listeners

Explanation

dB HL is referenced to the average normal threshold of hearing at each frequency, determined by normative data from otologically normal young adults. It is a relative, ear-referenced scale, not an absolute physical intensity scale.

Question 43Acoustics, Psychoacoustics, and Speech Science

A listener reports that a tone appears to rise in pitch when its intensity is increased. This phenomenon is best described as:

  1. Temporary threshold shift
  2. Loudness recruitment
  3. The upward spread of masking
  4. The dependence of pitch on intensity Correct answer.

Explanation

For mid-frequency tones, pitch typically rises slightly as intensity increases, a classic psychoacoustic effect showing that pitch is not determined by frequency alone. It reflects nonlinear processing in the cochlea.

Question 44Acoustics, Psychoacoustics, and Speech Science

Which acoustic measure is defined as the ratio of reflected to incident sound energy at a boundary?

  1. Transmission loss
  2. Absorption coefficient
  3. Reflection coefficient Correct answer.
  4. Reverberation time

Explanation

The reflection coefficient quantifies the fraction of incident energy or pressure reflected at an impedance boundary, and it is related to the absorption coefficient by conservation of energy. It is central to understanding room acoustics and impedance mismatches.

Question 45Acoustics, Psychoacoustics, and Speech Science

In a source-filter model of speech production, the vocal tract primarily determines which property of the radiated speech signal?

  1. The rate of vocal fold vibration
  2. The fundamental frequency of voicing
  3. The amplitude of subglottal pressure
  4. The formant frequencies of the resonances Correct answer.

Explanation

The vocal tract acts as an acoustic filter whose resonances produce formants, shaping the spectral envelope that carries vowel identity. The source (vocal folds) supplies the fundamental frequency and harmonic structure.

Question 46Acoustics, Psychoacoustics, and Speech Science

Two pure tones of 1000 Hz and 1004 Hz are presented simultaneously at equal level. A listener perceives a slow fluctuation in loudness. What is the beat frequency?

  1. 8 Hz
  2. 2 Hz
  3. 4 Hz Correct answer.
  4. 1002 Hz

Explanation

Beats arise from linear interference of two close frequencies, and the beat rate equals the difference between them: 1004 − 1000 = 4 Hz. The perceived fluctuation occurs at this difference frequency, not at the sum or average.

Question 47Acoustics, Psychoacoustics, and Speech Science

A sound has an intensity of 10^-4 W/m². What is its intensity level in dB IL, given the reference intensity of 10^-12 W/m²?

  1. 40 dB
  2. 120 dB
  3. 100 dB
  4. 80 dB Correct answer.

Explanation

Intensity level is 10 log10(I/I0) = 10 log10(10^-4/10^-12) = 10 log10(10^8) = 80 dB. Each factor of ten in intensity adds 10 dB, so eight decades give 80 dB.

Question 48Acoustics, Psychoacoustics, and Speech Science

A vowel has formants near 300 Hz, 2300 Hz, and 3000 Hz. Based on these formant values, which vowel is most likely?

  1. /ɑ/ as in 'father'
  2. /i/ as in 'beat' Correct answer.
  3. /ɛ/ as in 'bet'
  4. /u/ as in 'boot'

Explanation

Low F1 indicates a high tongue position and high F1 indicates a low tongue; F2 relates to tongue advancement, with high F2 for front vowels. The given low F1 near 300 Hz and high F2 near 2300 Hz therefore best fit the high front vowel /i/.

Question 49Acoustics, Psychoacoustics, and Speech Science

In a reverberant room, the reverberation time T60 is the time required for a sound to decay by how much after the source stops?

  1. 30 dB
  2. 6 dB
  3. 10 dB
  4. 60 dB Correct answer.

Explanation

T60 is defined as the time for the sound pressure level to decay by 60 dB after the source ceases, measured typically from a 5 dB to 35 dB decay window extrapolated. It is the standard descriptor of room reverberance.

Question 50Acoustics, Psychoacoustics, and Speech Science

A listener with a high-frequency sensorineural hearing loss reports difficulty understanding speech in background noise. Which psychoacoustic consequence most directly explains this difficulty?

  1. Reduced loudness recruitment
  2. Increased temporal integration time
  3. Elevated bone-conduction thresholds only
  4. Reduced frequency selectivity and widened auditory filters Correct answer.

Explanation

Cochlear hearing loss often broadens auditory filters, reducing frequency selectivity so that speech cues are smeared and more susceptible to masking by noise. This loss of fine spectral resolution underlies the common complaint of poor speech-in-noise performance.