Question

15.

a.Networks of Association - how semantic info is stored.

b. Explain this concept. Include the idea of a node.

c.Spreading activation – explain. Use the “ocean-moon” example in the text in your explanation.

d. Hierarchical organization of semantic networks. -Explain this concept.

Answer 1

• c)The Spreading Activation Model-Collins and Loftus (1975) developed the spreading activation model of semantic memory.It suggests that concepts and nodes are linked together with different levels of conductivity. The more often the two concepts are linked, the greater conductivity.
• Collins and Loftus assumed that semantic memory is organised on the basis of semantic relatedness or semantic distance. Nodes that get consistently activated together form stronger connections that make it easier to excite each other, when you look at the network they show this by having shorter links between nodes.
• The shorter the link, the closer the semantic relation, and so the faster the brain will be at making the connection between the nodes. Furthermore, the longer a concept is accessed, the larger the spread of activation.
• Spreading activation is the idea that when a concept is accessed activation spreads out from that node in all directions, as the node attempts to excite all the nodes around it. The higher the conductivity the faster it spreads down that link. Whenever a person thinks, hears or sees, a concept the appropriate node is activated.
• The model uses the analogy of neurons: nodes have an activation threshold, and it must be beat for it to fire.
• Whereas Collins & Quillian say that the connections were based on logic (set-subset relationships), Collins & Loftus say that the connections are based on personal experience and are not necessarily logical.  
• Advantages of the model are that it can explain the familiarity effect, the typicality effect, and direct concept-property associations. It’s biggest advantage is that it explains “priming”: you are more likely to retrieve information from memory if related information (the “prime”) has been presented a short time before.  
• The disadvantage is that you can’t predict reaction times in a verification task until you have mapped out the individual’s network of associations. The theory explains a lot but predicts very little.
• Due to time limit remaining questions can be asked as another question,they will be answered,thankyou for your cooperation