Psycholinguistics 03 Psychological Mechanisms Psychological Mechanisms • Memory – Function – Structure • Processing – Serial and parallel processing – Top-down and bottom-up processing – Automatic and controlled processes The Function of Memory • The purpose of having a memory is to store information for later use. What properties should a good memory have to accomplish these functions? – Encoding – Retrieval – Forgetting Encoding • Levels of processing: the experiment by Craik (1975) on the processing on visual appearance, sound of the word and the meaning of the word proved that these aspects result in different effects of processing (levels of processing) Encoding • Context effect: an object or event will be encoded differently in different contexts. The term context refers to any perceptions, sensations, or thoughts that was active at the time a given stimulus is encoded. Encoding • Principles of association: contiguity and frequency. According to the principle of contiguity, any two mental events that cooccur tend to become linked. But the actual likelihood of making the association depends on what Seligman (1970) called preparedness. A given species of animal may readily learn some associations but have great difficulty learning others. For a rat, 'light' 'shock', 'taste' 'the experience of becoming nauseated' are easier to associate than the other way round. Encoding • The principle of frequency or practice: each time two items appear contiguously, the association between them is strengthened. Encoding • Associative models: the idea that memory consists of association between mental entities underlies associative models of human memory. In such models the contents of memory consist of mental representations of items and their associative connections. A basic assumption common to associative models of memory is that activation in one part of the network spreads over time to associated (linked) items. (Collins and Quillian, 1989) Retrieval From Memory • The principle of content addressing is central in memory retrieval. Content addressing means starting retrieval with part of the content to be remembered which provides an 'address' to the place in memory where identical or similar material is located. But there are some kinds of information that cannot be used as retrieval address, even though the information is in memory. E.G. What word for a family relationship ends in w? Retrieval From Memory • Retrieval is a two-stage process: the first stage provides a large amount of material much of which is only marginally related to the initial stimulus or query; The second stage then selects according to some additional criteria, before passing the result to a third stage. Retrieval From Memory • Remembering is not restricted to deliberate reminiscence: rather, it is a continuous and essential accompaniment to thought. Just as we may fail to retrieve a relevant memory, we also retrieve memories unintentionally. Forgetting: Planned Obsolescence? • Use it or lose it: memory decays over time. The forgetting process selects appropriate material to discard by disuse. • Interference between memories: memory changes occur when new information is merged with or mixed up with previously known information; Sometimes the new information becomes distorted, but sometimes the older information is changed. Forgetting: Planned Obsolescence? • Benefit of interference: • (A) it promotes the development of general memories that summarize experience, or updates memory as revised information is obtained. • (B) it is helpful to have the most recent occasion dominate memory for previous instances. The role of recency mechanism is to orient us in time and space: where we are and how we got there, what we have done recently. Structure of Memory Sensory Stores • The sensory stores take in the variety of colors, tones, tastes, and smells that we experience each day and retain them, for less than half a second, in a raw, unanalyzed form. • Researchers suggest that there is an independent sensory store for each sensory system, e.g. visual memory, auditory memory, conceptual memory. Sensory Stores • Ordinarily we continue to look at the same point for 200 or 300 msec., Which is enough time to recognize most objects and scenes. The iconic memory is wiped out by a new stimulus (an effect called backward masking). It is well that the next stimulus does not mask the last one, or we would see double images. The only blanks in normal viewing occur when we blink, or during the 30 msec. That it takes to move our eyes from one spot to the next; Iconic memory may help to bridge those gaps. Sensory Stores • Auditory sensory store has a longer duration (2 to 4 seconds). Working Memory (Short Term Memory) • A temporary holding place for the cognitive acts on the information. • Size: limited, 7±2 units • Duration: limited, 10 to 20 seconds Working Memory (Short Term Memory) • It preserves information in a speechlike or auditory form. • It is severely limited in how much information it can hold. Working Memory (Short Term Memory) • Continuous rehearsal (rehearing) can maintain the contents of the memory indefinitely. • Working memory has both storage and processing functions. Both of them compete for processing capacity, the total amount of cognitive resources devoted to a task. He reckons the current account deficit will narrow to only # 1.8 billion in September Chunking Move your cursor over picture A and look at it for a few seconds, you will probably have trouble remembering how many figures you saw. Now move your cursor over Picture B and look at it for a few seconds too. You should be able to recall now how many figures are there. Although there are as many figures in B as in A, they are grouped, or chunked, in B, and are thus easier to count and remember. Picture Permanent Memory • The repository of our knowledge of the world. It holds all of the information we have retained from the past that is not currently active. Permanent Memory • The dominant form of information in long-term memory is conceptual, in the form of propositions, because that is ordinarily the most important information about events and therefore receives more attention and processing time than sounds or appearances. Permanent Memory • Two types of permanent memory (Tulving: 1972): semantic memory and episodic memory • Semantic memory: organized knowledge of words, concepts, symbols and objects, e.G. Motor skills, general knowledge, spatial knowledge, social skills. • Episodic memory: traces of events that are specific to a time and place. Memory and Language Processing • Sensory store: pattern recognition occurs when information from one of the sensory stores is matched with information retrieved from permanent memory. • Working memory: chunk the words into grammatical constituents, process the meaning. • Permanent memory: store knowledge and represent the ongoing discourse, hold information from previous sentences to establish coreferences. Summary of Memory Types Information stored Duration Sensory Memory in a raw, unanalyzed form 1/3 to several seconds Working Memory in a raw, unanalyzed, a few seconds (e.g. form, processing verbal information: involved remains 2 seconds, lost in 39 seconds) Permanent Memory in the form propositions of forgetting happens Discussion • In light of the memory theory, explain the cognitive process of the following: –Passage reading –Read questions in a reading comprehension test –Listening test of a statement with multiple choice questions, a passage with multiple choice questions –Writing a composition Issues in Language Processing • • • • Serial and parallel processing Top-down and bottom-up processing Automatic and controlled processes Modularity Serial and Parallel Processing • Serial processing: deal with one task at a time. • Parallel processing: deal with multiple tasks at a time • Rumelhart’s test shows the context helps decide the identity of the obscured letter. And thus proves the parallel processing (fig. 3-2) . Top-down and Bottom-up Processing • Bottom-up processing: from the lowest level to the highest level • Top-down processing: information at the higher levels may influence processing at the lower levels. Automatic and Controlled Processes • Tasks that draw substantially from the limited resources are controlled tasks and the processes involved are controlled processes. • Tasks that do not require substantial resources are automatic tasks and the processes involved are automatic processes. • Automatic tasks are not related to the age of the individual or to the strategy employed. Automatic and Controlled Processes • Certain automatic tasks appear to be biologically built into our cognitive equipment, e.g. frequency counter. • Other automatic processes are the result of extensive practice. • Language processing can be automatic (recognition of common words) or controlled (parsing of sentences). Modularity • Two meanings of modularity • An independent processing system usually taken as a whole (Chomsky) or as interconnections between language and cognitive processes, domain specific. • Linguistic subsystems (e.g. semantics, syntax) operate independently rather than interactively. Schema • Much language is contextually interpreted. That is, it relates to some integrated and (usually) coherent domain, and only makes sense within that domain. Our current term for this domain to which the discourse relates is schema (plural schemata). Gestalt Psychology • Gestalt psychology is based on the observation that we often experience things that are not a part of our simple sensations. We see what is not there. • The word Gestalt means a unified or meaningful whole. • There is only one image here, and yet, by changing nothing but our attitude, we can see two different things. Example of Schema A: Did you order it? B: Yeah, it will be here in about 45 minutes. A: Oh... Well, I've got to leave before then. But save me a couple of slices, okay? And a beer or two to wash them down with? • What are they talking about? Schema • Schemata are composed of generic or abstract knowledge; used to guide encoding, organization, and retrieval of information. • Schemata reflect prototypical properties of experiences encountered by an individual, integrated over many instances. • A schema may be formed and used without the individual's conscious awareness. • Although schemata are assumed to reflect an individual's experience, they are also assumed to be shared across individuals [in a culture?]. • Once formed, schemata are thought to be relatively stable over time. • We know more about how schemata are used than we do about how they are acquired.