Neuro Exam 2 Bolded

spectrotemporal analysis

The computation of which sound frequencies are modulated at which rates over time.

phonological neighborhood density

The size of a given word’s network of similar-sounding words.

Wada procedure

A way to temporarily shut down an entire hemisphere by injecting sodium amobarbitol into either the left or the right carotid artery.

word deafness

A disorder in which speech perception is impaired, despite intact hearing and sometimes even intact recognition of nonspeech sounds.

A fork in the river:

Separate streams for “what” and “how” during speech perception

Ventral

What

Dorsal

How

lemma

An abstract word node that not only intervenes between semantics and phonology, but also specifies grammatical information (e.g., cat is a count noun that can be either singular or plural).

verbal short-term memory (STM)

A memory system that allows a person to keep words in an active state for a relatively short period of time.

digit span task

A task that measures a person’s verbal STM capacity by determining the longest string of arbitrary digits that they can repeat correctly.

lexical concept

A unit that integrates the multifarious semantic features that constitute the meaning of a particular word.

lemma

An abstract word node that not only intervenes between semantics and phonology, but also points to morphosyntactic features like grammatical category.

syllabary

A long-term repository of precompiled, automatized motor programs for high-frequency syllables.

auditory target representation

A representation of how an utterance is expected to sound.

somatosensory target representation

A representation of how an utterance is expected to feel, in terms of tactile and proprioceptive (i.e., body-part positional) sensations.

Speech Sound Map

A repository of acquired speech sound representations (phonemes, syllables, or syllable sequences) that serve as the starting point for speech motor control. This component corresponds to the phonetic encoding stage of the Lemma Model and is similarly localized in two general regions of the left frontal lobe. The first, lower region extends from BA44 into the vPrCG and anterior superior insula, whereas the second, upper region is centered in midPrCG.

Articulator Map

A set of nodes that represent the major components of the vocal tract (larynx, lips, jaw, and tongue), that specify the time series of movements necessary to produce a particular utterance, and that have a rough somatotopic organization in the ventral primary motor cortex bilaterally.

spastic dysarthria

A disorder that involves reductions of the speed, strength, range, and accuracy of articulatory movements, and that is manifested in its most severe form following bilateral damage to the ventral primary motor cortex, or to the underlying white matter projections from those cortical areas to subcortical nuclei.

ataxic dysarthria

A disorder of speech motor control that has been linked with damage to lobule VI of the cerebellum, and that involves uncoordinated and poorly timed articulation, equal stress on syllables, vowel distortions, and excess loudness.

Initiation Map

A module that sends a “go” signal to prepared speech motor commands, and that resides in the supplementary motor area (SMA) bilaterally, with modulatory influences from the basal ganglia.

akinetic mutism

A neurological condition that follows from bilateral damage to the supplementary motor area (SMA) and involves a virtually complete loss of voluntary speech and movement.

hypokinetic dysarthria

A disorder of speech motor control that is associated with the type of basal ganglia dysfunction found in Parkinson's disease, and that is characterized by delays in starting and stopping speech, a reduced range of pitch and volume, and a tendency for syllables to run together. It may reflect an underactive Initiation Map.

hyperkinetic dysarthria

A disorder of speech motor control that is associated with the type of basal ganglia dysfunction found in Huntington's disease, and that is characterized by variable speech rate, imprecise articulation, and sudden involuntary bursts of speech. It may reflect an overactive Initiation Map.

forward model

A specification of how certain motor commands should give rise to certain sensory consequences.

inverse model

A specification of how certain sensory consequences can be achieved by executing certain motor commands.

Auditory Target Map

A module that subserves auditory target representations (i.e., acoustic expectations) during speech production, and that resides in the pSTG bilaterally.

Auditory State Map

A module that represents speech-related auditory input (including self-generated utterances), and that resides in Heschl’s gyrus as well as anteriorly and posteriorly adjacent superior temporal areas bilaterally.

Auditory Error Map

A module that computes discrepancies between the anticipated and the actual sounds of self-generated utterances, and that resides in the pSTG and planum temporale bilaterally.

Feedback Control Map

A module that adjusts or updates articulatory commands in light of sensory feedback, and that resides in the right posterior IFG.

Somatosensory Target Map

A module that subserves somatosensory target representations (i.e., tactile and proprioceptive expectations) during speech production, and occupies posterior parts of the ventral postcentral gyrus bilaterally.

Somatosensory State Map

A module that processes tactile and proprioceptive feedback during speech production, and is represented in a somatotopic manner in anterior parts of the ventral postcentral gyrus bilaterally.

Somatosensory Error Map

A module that computes discrepancies between the anticipated and the actual tactile and proprioceptive sensations associated with speech production, and that depends on several cortical regions bilaterally: posterior parts of the ventral postcentral gyrus; anterior parts of the adjacent supramarginal gyrus; and posterior parts of the insula.

cranial nerves (CNs)

A set of brainstem nuclei that provide motor and sensory innervation for the head and neck.

corticobulbar pathway

Projections from neurons in the motor cortex to the cranial nerves.

upper motor neurons (UMNs)

Another term for neurons in the motor cortex.

lower motor neurons (LMNs)

Another term for cranial nerves.

flaccid dysarthria

An articulatory disorder that involves slow rate, breathy voice, hypernasality, impaired consonant production, and monotonous pitch and loudness. It results from damage to the cell bodies and/or axons of the cranial nerves that activate the muscles of the vocal apparatus.

saccade

An eye movement from one location in a scene to another location.

fovea

The small circular space of maximal visual acuity at the center of fixation.

Local Combination Detector (LCD) Model

A neurally based framework for characterizing reading that posits multiple levels of feature detectors, hierarchically organized in such a way that increasingly larger fragments of printed words are represented at each successive level.

receptive field

The preference of a neuron for particular visual properties in a particular location of the visual field.

alexia

A reading disorder with two subcategories: One subcategory includes patients who cannot even recognize single letters, let alone complete words. The other subcategory includes patients who cannot read whole words with just one quick glance, but must instead decipher each sequential letter in a slow and deliberate manner and then put all the pieces together.

Neuronal Recycling Hypothesis

The idea that culturally acquired abilities like reading invade evolutionarily older brain circuits and inherit many of their structural and functional constraints. According to this view, the VWFA is ideally suited to represent the spelling patterns of printed words because it is apparently designed to register complex combinations of spatially fine-grained shapes.

phonological dyslexia

A disorder of reading aloud in which patients perform significantly worse on pseudowords than real words.

surface dyslexia

A disorder of reading aloud in which patients perform significantly worse on irregular words, especially low-frequency ones, than on regular words and pseudowords.

deep dyslexia

A disorder of reading aloud in which patients are impaired on pseudowords as well as real words, with errors on the latter being visual, phonological, semantic, and morphological in nature and typically worse for abstract than concrete items.

phonological dysgraphia

A disorder of writing to dictation in which patients perform significantly worse on pseudowords than real words.

surface dysgraphia

A disorder of writing to dictation in which patients perform significantly worse on irregular words, especially low-frequency ones, than on regular words and pseudowords.

deep dysgraphia

A disorder of writing to dictation in which patients are impaired on pseudowords as well as real words, with errors on the latter often being semantic in nature and worse for abstract items.