Conceptual systems

Question 1

what is a concept?

Answer 1

• “Mental representations of categories of objects in the world— make up much of the contents of our thoughts”
• We use them to:
  
  • Underlie thought and language
  • Made predictions/have expectations about the world

Question 2

what are the parts of a concept?

Answer 2

• Concept
  
  • Mental representation of categories of objects in the world e.g. dog, mammal, pet
• Semantic memory
  
  • Concepts + meaning help us:
    
    • recognise objects, anticipate behaviour, Perform functions
  • This general knowledge of meaning = semantic memory
• lexical semantics
  
  • meaning of individual words

Question 3

Are categories and concepts the same?

Answer 3

• Categories = how we group objects in physical world
• Concepts = mental representation of categories
• Conceptually Vegetable
  Categorically Botanical classification: Fruit

Question 4

what are amodal theories?

Answer 4

• Argue concepts:
  
  • Amodally encoded
  • Abstract idea of a “dog”
• Mental representation not outside sensorimotor or affective modalities

Question 5

what is strong embodiment?

Answer 5

• Cognition is affected by the body, occurs within the surrounding environment, involves perception and action
• Don’t need mental representations
• We simply simulate the motor/perceptual activity that is generated when encountering those “concepts” or “category members”
  - e.g. for the verb “throw” we embody the action of throwing
  - e.g. for the noun “dog” we draw on what the dog looks like, its bark, how it runs

Question 6

what is the evidence for embodiment? (1)

Answer 6

• Reading action-related words (e.g. lick, pick or kick) and sentences produces increase activation in cortical regions associated with performing the relevant movements (Hauk, Johnsrude, & Pulvermüller, 2004).

Question 7

what is the evidence for embodiment? (2)

Answer 7

• Right- and left-handers exhibit increased activation in the premotor areas contralateral to their dominant hands when carrying out a lexical decision task on manual-action verbs (e.g. throw) (Willems, Hagoort, & Casasanto, 2009).

Question 8

what is the evidence for embodiment? (3)

Answer 8

• Reading odour-related words (e.g., cinnamon) elicits increased activity in olfactory regions, when compared to neutral words (Gonzalez et al., 2006).

Question 9

what is the evidence for embodiment? (4)

Answer 9

• Recognition of words highly associated with auditory features (e.g., telephone) elicits activity in areas of the auditory association cortex that are active during sound perception (Kiefer, Sim, Herrnberger, Grothe, & Hoenig, 2008).
  
  • This activity is not found for words highly associated with visual or motor features.
  • Event-related potentials (ERPs) recorded with the same stimuli suggest that this increased activity begins around 150 ms after word onset (Kiefer et al.,
    2008).

Question 10

what is the argument against embodiment?

Answer 10

• Goldinger et al. (2016)
  
  • We have “rich conceptual structures that guide thinking” E.g. “what is a doggier dog, dachschund or golden retriever?”
  • “Where might you go for an unpleasant vacation?”
• Hard to explain these by bodily states or actions alone
• Think about common metaphors like “grasping an idea” or “feeling down.” How do these phrases relate to physical experiences

Question 11

what is the hybrid account?

Answer 11

• Embodiment alone is not enough
• Conceptual representations critically depend on abstract representations, embodiment only contributes

Question 12

what is the “hub and spoke” model?

Answer 12

• Anterior Temporal Lobe (ATL) is a semantic hub, crucial for our amodal representations
• Connects to the “spokes” – connections to sensory and motor perception

Question 13

what is the evidence ATL semantic hub?

Answer 13

• Atrophy of ATL - “semantic dementia”

Question 14

what is the evidence to support for a ‘Hub’ from Semantic Dementia?

Answer 14

• Semantic Dementia (SD) patients have atrophy of the anterior temporal lobes (ATL) and have been a rich source of data for the hub view
• Semantic dementia is a progressive degenerative disease
• Bilateral atrophy of anterior temporal lobes but often greater in the left hemisphere

Question 15

what is the link with the Anterior Temporal Lobe and Semantic Dementia?

Answer 15

• Selective Semantic Deficits
  
  • e.g., naming, categorization, word-picture matching, object recognition
• Other functions are normal:
  
  • Memory (WM/LTM)
  • Visuospatial
  • Syntactic

Question 16

what is semantic dementia?

Answer 16

• Impaired semantic knowledge but other cognitive abilities remain intact (at least in early stages)
• First sign is inability to name objects
  
  • Anomia: Inability to name objects
• Speech is otherwise fluent and grammatical.
  
  • Progressive
  • Form of dementia
  • Part of frontotemporal dementias

Question 17

what are the key terminologies?

Answer 17

• Dementia: is a syndrome (a group of related symptoms) associated with an ongoing decline of brain functioning (NHS website)
• Aphasia: is a language disorder caused by damage in a specific area of the brain that controls language expression and comprehension (John Hopkins medicine)
• Aphasia can come from stroke, brain injury, brain tumour, progressive degenerative neurological conditions e.g. dementia

Question 18

what are hub predictions?

Answer 18

• Localised damage to “hub” should result in deficits in conceptual knowledge that are independent of the modality presented
• Deficits should NOT depend on the task’s:
  
  • Input modality (object, picture, word, taste, sound)
  • Output modality (naming, drawing, use)
• Are the impairments of semantic dementia patients consistent with these predictions?

Question 19

what is Picture replication from memory in SD
Bozeat (2003)?

Answer 19

• Task modalities:
  
  • input = picture
  • Output = picture
• Delayed-copy drawing
  
  • Model picture presented and then removed
  • After 10sec delay asked to draw the object from memory
  • Nonverbal (input and output)

Question 20

what is Picture naming in semantic dementia (Hodges et al (1995))?

Answer 20

• Given pictures to name
  
  • Task modalities:
  • Input = picture
  • Output = word
  • • = Correct Response
• Performance over time (progressive condition)
• Seem to be reverting to the basic category or incorrect answer

Question 21

what is basic level advantage?

Answer 21

• Healthy adults show a basic-level advantage
  
  • Tend to name objects at Basic level
  • More accurate and quicker in categorization tasks
  • Children learn basic level first

Question 22

Why might basic and specific levels be
lost in semantic dementia?

Answer 22

• SD, progressively, and selectively losing access to the representation of distinct features
• General categories = least feature specific
• General features = occur more frequently, therefore have a stronger more robust representation

Question 23

Is the ATL really a concept hub?

Answer 23

• Simmons & Martin (2009)
• Potential issues:
  
  • Virtual lesion to ATL alters activity in remote sites
  • Semantic Dementia – Damage not restricted to ATL
  • Often extends to amygdala and frontal loves
  • Resection of area due to epilepsy rarely leads to domain-general semantic memory impairments.
  • Although usually unilateral
  • Focal ATL damage associated with selective semantic memory deficits.
  • Person specific information
  • fMRI data suggests that ATLs engaged in general social conceptual processing
  • Although, ATL susceptible to artifacts

Question 24

what does the hub do?

Answer 24

• Organises atypical tokens into categories and hierarchies.

Question 25

ATL is part of the “hub” and “spoke” model?

Answer 25

- Our representations of concepts are closely linked to: - The words associated with them - The actions made by them or in relation to them - The sounds they make - Their form - shape & colour - How they move - The “hub” links this information together and is likely important for connecting the different forms of information “spokes” with an amodal representation