Semantic memory (Additional)

Question 1

What is the main debate in semantic memory structure?

Answer 1

Whether it is one integrated system (Hub-and-Spoke) or multiple independent systems (e.g., Sensory/Functional theory).

Question 2

What evidence supports the Hub-and-Spoke model?

Answer 2

Semantic dementia (SD) causes global, cross-modal semantic loss; ATL damage impairs conceptual integration; rTMS to ATL temporarily impairs semantic tasks.

Question 3

What is reverse imageability and how does it support the Hub-and-Spoke model?

Answer 3

Patients with SD often do worse on concrete, sensory-rich items than abstract ones. Abstract words (e.g., idea, truth) don’t rely on sensory features, so they may be less affected by the failure of hub integration therfore they are easier to access even though they should be harder.

Question 4

What evidence supports the Sensory/Functional Theory?

Answer 4

Category-specific deficits, double dissociations, reverse imageability effects, and Plaut & Shallice (1999) computational modelling.

Question 5

What is a key criticism of the Sensory/Functional Theory?

Answer 5

Oversimplified — many items use both sensory and functional features (e.g., musical instruments, vehicles).

Question 6

What is the difference between semantic dementia and semantic aphasia?

Answer 6

SD = storage failure (ATL); consistent loss. SA = access failure (frontoparietal); inconsistent performance, cue-sensitive.

Question 7

Why is the Hub-and-Spoke model preferred overall?

Answer 7

It integrates distributed and feature-based findings, explains both general and selective deficits, and is backed by SD, imaging, and TMS evidence.

Question 8

What is the best conclusion about semantic memory structure?

Answer 8

It’s best understood as a single, integrated system with distributed specialised components.