Unit 11 - The Speaking Brain Flashcards
What is the phonological lexicon?
A store of the abstract speech sounds that make up known words
What is lexical access?
The process of matching a perceptual description of a word onto a stored memory description of that word
What are two four that have been considered as potential units for speech representations?
Phonemes
Acoustic features of speech such as voicing, stops, formant frequencies, etc.
Syllables
Stress patterns
What is the primary piece of evidence against a phonemic level in lexical access?
Double dissociation between discriminating between phonemes and comprehending spoken words
What is the general consensus on word recognition?
Multiple features of the acoustic signal contribute to word recognition.
These features vary in temporal duration and psycholinguistic unit size.
Word recognition is not reliant on a single source like phonemic information.
What is stress?
An increase in the activity of the vocal apparatus of a speaker that aids the segmentation of the speech stream into words
What is a phoneme?
A minimal unit of speech that serves to distinguish between meanings of words
What is a syllable?
A cluster of phonemes that are centred on a vowel sound
What is a morpheme?
The smallest meaningful unit in the grammar of a language
What is a prosody?
Melodic aspects of spoken language such as stress, intonation, and emotion
What are pragmatics?
The way in which language in used in practice, such as implied or intended meaning
What is a preposition?
Indicates a connection between two other parts of speech, such as “to”, “with”, “by”, “from”
What is a proper noun?
A name
What are function / closed class words?
Words with little lexical meaning that express grammatical relationships:
-E.g, pronouns, prepositions, “the,”
“and.”
What is a cohort model in lexical access? What is its function? Why is it useful?
A large number of spoken words are initially considered as candidates but words get eliminated as more evidence accumulates
A theory for how spoken word recognition takes place
Since the acoustic information needed to identify a word is revealed over time
What is the uniqueness point? What does it determine?
The point at which the acoustic input unambiguously corresponds to only one known word
The time taken to recognise a word
What are two other factors that impact word recognition?
Word frequency (how common a word is)
Word imageability
What is word imageability? When does it impact word recognition most?
The extent to which a word can evoke a concrete image
In situations with high cohort competition
What is the N400? What does it suggest? Does it only take place for spoken words?
An event-related component in EEG found when a word meaning appears out of context or unexpectedly
That both word and world knowledge are relevant to the word recognition process
No, it can take place through a number of mediums, but is more common for spoken words
Are lexical access and contextual integration separate and discrete stages in speech recognition? What is the evidence for this?
No, as evidenced by the fact that the language system does not wait for the uniqueness point to be reached before it can generate an N400.
What is one agreed-upon factor of different theories on semantic memory, and what are some factors that are not agreed upon?
That concepts are composed of a network of constituent features
What does the hierarchical view of semantic memory entail? What are three pieces of evidence for this model?
Hierarchical organization: superordinate (animal, transport), ordinate (bird, car), subordinate (canary, Ferrari).
Robin is classified as a bird faster than as an animal due to hierarchy.
fMRI shows lateral temporal lobe activation varies with information specificity.
Anterior temporal lobe damage: patients can make superordinate but not item or subordinate classifications.
What are proper names / nouns? What is their correlation to the hierarchical view of semantic memory?
Types of nouns denoting a unique entity such as people and place names, e.g., “Donald Trump” or “Washington DC”
Can only be represented at subordinate level
What does “amodal” mean? What is believed to be amodal?
Not tied to one or more perceptual system
Semantic memory
What is the symbol grounding problem in linguistics? What could be one way of mitigating this problem?
The problem of defining concepts without assuming some preexisting knowledge
Deriving conceptual knowledge from the associated sensorimotor experiences rather than abstract definitions
What is embodied cognition?
The idea that the body (its movement, or internal state) can be used in cognition (e.g., to understand words or social situations)
Where does the collection of different semantic features that make up a concept reside according to fully grounded models of semantic memory? For instance? What is the process of pattern-completion in this context?
Information is stored in different channels based on acquisition.
Semantic memory of a telephone:
-Auditory regions for sound
-Visual regions for appearance
-Action-related regions for usage
Interconnected domains: activating one triggers all others.
What could be the importance of motor areas for semantic memory? How about sensory areas? Is semantic memory grounded solely in these areas?
Retrieval of action-based concepts depends on body and motor areas.
High sensory feature concepts activate related sensory brain regions.
However, the argument is that semantic memory is primarily amodal, with modality-specific representations as by-products.
What is the hub-and-spoke model?
A model of semantic memory that contains both amodal concepts (the “hub”) and semantic features that are grounded in the sensory, motor and bodily cortex (the “spokes”)
What are the “spokes” in the hub-and-spoke model?
Regions involved in sensory and bodily processes that store semantic information
Three possibilities for whether different kinds of semantic categories have different neural substrates in the brain:
Category groupings are explicitly learned
Categories are learned via statistical regularities
Categories are hardwired
What is the “hub” in the hub-and-spoke model? What are its functions?
A central, amodal, semantic system that all of the spokes connect to,
Allows exceptional items to be categorised and superficially different entities to be grouped together.
What is some evidence for this model?
Patients with semantic dementia can make category distinctions based on feature probabilities (the “spokes”).
They struggle with distinctions based on conventional knowledge, exceptions, and learned taxonomies (the “hub”).
What is the sensory-functional distinction? Provide an example. Are categories emergent properties in this model?
Semantic features are clustered in the brain by use and physical properties.
Animals, fruits, and vegetables are defined more by sensory properties.
Inanimate objects are defined by their functions.
These clusters form because features tend to co-occur.
What is Wernicke’s aphasia? What did Wernicke divide the spoken forms of words into? Damage to which of the centres causes Wernicke’s aphasia?
A type of aphasia traditionally associated with damage to Wernicke’s area and associated with fluent but nonsensical speech and poor comprehension
Input centres termed “auditory images” and output centres termed “motor images”
Damage to the auditory images or input centre
What is an alternative view to categories being emergent properties? What is it evidenced by?
Certain categories are evolutionarily hardwired into human brains: animals, plant life, other humans, tools.
Patients with animate category-specific deficits may not be impaired in answering sensory versus functional questions about animals or objects.
What is the main problem of these models?
That Broca’s and Wernicke’s aphasia are not well characterised as selective disorders of input or output, as both disorders can cause issues in both inputs and outputs
What is Broca’s aphasia? Damage to which of the centres causes Broca’s aphasia?
A type of aphasia traditionally associated with damage to Broca’s area and linked to symptoms such as agrammatism and articulatory deficits
Damage to the motor images or output center
What is meant by syntax? What is its function?
The order and structure of the words within a sentence
Enables the listener to figure out who is doing what to whom
What is the currently believed role of Broca’s area in sentence processing? What is the evidence for this?
Syntactic processor
Symptoms of agrammatism and impaired sentence comprehension for those with damage to Broca’s area
What was Lichteim’s concept centre?
He argued that the motor and auditory centres are linked by two routes, both of which pass through the concept centre directly and indirectly
What is agrammatism?
Halting, “telegraphic” speech production that is devoid of function words (e.g., of, at, the, and), bound morphemes (e.g., -ing, -s), and often verbs
Are there any other areas responsible for syntax comprehension? If so, which?
Yes, the temporal lobes
What are the two functional subdivisions of Broca’s area?
Posterior division BA44 and anterior portion BA45
For which types of sentences is sentence comprehension worse for Broca’s aphasics?
Reversible (e.g., cat is biting the dog) and semantically improbable (e.g., the baby is scaring the lion) sentences
What are some of the functions of BA44 (posterior)? What is its proposed functioning specifically?
Processing of hierarchical structures
Sequencing of behaviour in general
Higher-level motor planning of speech
Mirror system for speech and other gestures
Judging grammar
Generates predictive signals to other brain areas about expected words, monitors whether the prediction is met.
How about BA55 (anterior)?
Working memory
Control of semantic memory
Judging a word’s correctness
Is syntax independent from semantics?
Patients with semantic dementia can still produce grammatical sentences.
However, judging the syntax of certain phrases relies on semantic understanding.
What are garden-path sentences? What do they evidence? What is one way to avoid being led up the “garden path”? What does this imply?
A sentence in which the early part biases a syntactic interpretation that turns out to be incorrect
Structure-driven parse of a sentence as opposed to a semantically driven-one
Context, implying that semantics are also necessary for parsing
What is parsing?
The process of assigning a syntactic structure to words
What is the link between syntactic complexity and working memory?
Greater syntactic complexity tends to lead to greater working memory loads
What is P600? What does this, together with N400, support?
An event-related brain potential (ERP) typically associated with the processing of grammatical anomalies
The idea that syntax and semantics are separable
Is syntax independent from working memory functionally?
Brain-damaged patients with phonological short-term memory deficits can produce and comprehend many sentences adequately
Others show clear deficits when syntactically complex sentences are presented
What is the process of lexicalisation in speech production?
The selection of a word based on the meaning that one wishes to produce
Three types of information that need to be retrieved in speech production:
Knowledge of the listener regarding the topic
Grammatical properties of words
Actual form of words in terms of constituent syllables, phonemes and articulatory patterns
What are spoonerisms?
A type of speech error in which initial consonants are swapped between words
What are malapropisms? What idea is this commonly used to support?
A speech error that consists of a word with a similar phonological form to the intended word
The notion of competition between similar words during normal word retrieval
What is inner speech? What do they tend to include?
Use of words or images without audible or physical speaking (in one’s head)
Word-level exchanges
What is the Freudian slip?
The substitution of one word for another that is sometimes thought to reflect the hidden intention of the speaker
What is the tip-of-the-tongue phenomenon? What is it caused by? What does this suggest?
A state in which a person knows, conceptually, the word that he or she wishes to say but is unable to retrieve the corresponding spoken form
Knowing some sorts of information about the object, but not all of it
That words are not retrieved in an all-or-nothing manner but rather that different aspects of a word can become available at different stages and relatively independently from each other.
What is lexeme?
The phonological code that drives articulation
What is anomia? What can it result from (two types)?
Word-finding difficulties
Either semantic difficulty in distinguishing between different concepts
OR
Difficulty in retrieving the phonological information to articulate it
What is meant by lemma?
A modality-independent, word-level entry that specifies the syntactic components of the word
What is an important, contradicting assumption of other models?
That multiple kinds of information (semantic, lexical, phonological) are active at the same time, not in discrete stages
What are two steps into which the process of getting from a conceptual level of representation to a phonological word (for spoken word retrieval) has been divided?
Firstly, lexicalisation with retrieval of syntactic features (retrieving a lemma)
Secondly, the retrieval of a lexeme representation
Are the two above stages considered discrete? What does this mean?
Yes, and it means that lexeme retrieval does not begin until lemma selection is complete.
Which areas of the brain have been found to be active during speech perception and production? Are these active in discrete stages? Which area(s) were activated during speech production?
Auditory regions, Broca’s area and motor regions
No
Motor regions and auditory regions (because of ppl hearing their own voice)
What is apraxia for speech? Damage to which part of the brain leads to this?
Difficulties in shaping the vocal tract, leading to distortions in the production of consonants, vowels and prosodies
Insula cortex
What is dysarthria? Damage to which part of the brain leads to this?
Impaired muscular contractions of the articulatory apparatus
Basal ganglia, cerebellum
