GR

Untitled Flashcard Set

Psychology chapter 6

Memory: the ability to store and retrieve information

        Includes conscious recollections but also the ways in which responses/behaviors are modified by experience

        Psychologists have identified different types of memory that rely on different brain circuits, or systems, for storage and expression

The case of H.M.

        Suffered from severe epileptic seizues originating in the temporal lobes

        In 1953, H.M.’s doctors removed parts of his medial temporal lobes, including the hippocampus

        The surgery had an unexpected side effect: H.M. lost the ability to remember new information for more than a few moments

        Psychologist Brenda Milner followed his case for 40 years, but had to introduce herself to him every time they met

 

Amnesia- memory loss

        Amnesia: a deficit in long-term memory, resulting from disease, brain injury, or psychological trauma, in which the individual loses the ability to retrieve vast quantities of information

        Retrograde amnesia: the loss of previously stored memories, including events, people, and personal information

        Anterograde amnesia: inability to encode or store new memories

        H.M. had a classic case of anterograde amnesia; he could remember old information, but after his surgery he lost the ability to form new memories.

 

Different brain regions support different memory systems

        Research with patients like H.M. helped psychologists identify different types of memory and the different brain circuits they rely on for storage and retrieval

        Implicit Memory: Memory that is expressed through responses, actions, or reactions

        Explicit Memory: Memory that is consciously retrieved

 

Priming

        Types of Priming

        Repetition priming: repeating a stimulus enhances response time

        Perceptual priming: enhanced response time to a stimulus is improved when presented with similar stimuli

        Conceptual priming: enhanced response time to a stimulus that is conceptually linked

        Keane and colleagues study:

        H.M.: could not remember the words shown earlier but showed perceptual priming

        L.H. (bilateral occipital lobe damage): could remember the words presented earlier but no perceptual priming

 

Semantic and episodic memory

        Episodic memory: memory for one’s past experiences that are identified by a time and place

        Semantic memory: memory for knowledge of facts independent of personal experience

        Evidence that episodic and semantic systems of explicit memory are separate can be found in cases of brain injury in which semantic memory is intact even though episodic memory is impaired (e.g., H.M.).

 

Memory processing stages

        Encoding: in which memories are acquired

        Storage: which involves consolidation

        Retrieval: releasing memory from storage to either be consciously experienced/declared or influence behavior

 

Sensory memory is brief

  • Sensory memory: a memory system that very briefly stores sensory information in close to its original sensory form

    • Sensory memory consists of brief traces on the nervous system that reflect perceptual processes.

    • Visual sensory memory is called iconic memory.

    •  Auditory sensory memory is called echoic memory.

    • Variable from person to person but Sperling concluded that sensory memory persists for about one-third of a second and then progressively fades.

Working memory is active

  • Material is passed from sensory memory to short-term memory. More recently, psychologists have come to think of short-term memory as working memory.

    • Short-term memory: a memory storage system that briefly holds a limited amount of information in awareness

    • Working memory: an active processing system that keeps different types of information available for current use

      • Information remains in working memory for about 20 to 30 seconds unless you actively prevent it from disappearing by thinking about or rehearsing the information.

  • Memory span refers to the amount of information held in working memory.

  • George Miller noted a typical limit of 7 items (+/– 2) in working memory, although more recent evidence suggests it may be limited to as few as 4 items.

    • Chunking can increase the amount of information that can be maintained

 

Long term memory

  • Long-term memory: the storage of information that lasts from minutes to forever

    • Long-term memory enables you to remember nursery rhymes from childhood, the meanings and spellings of words you rarely use, what you had for lunch yesterday, and so on.

 

Distinguishing long term memory

  • The distinction between working memory and long-term memory has been demonstrated by studies that investigated the serial position effect.

    • Serial position effect: the ability to recall items from a list depends on the order of presentation, with items presented early or late in the list remembered better

      • Primacy effect: better memory for items at the beginning of the list (reflects long-term memory)

      • Recency effect: better memory for the items at the end of a list (reflects working memory)

 

Slow consolidation can be beneficial

  • Consolidation involves a gradual process of strengthening neural connections/memories

    • Why would memories not be stored instantly?

    • The gradual process of strengthening connections between neurons results in some events being stored and others forgotten

      • Important, or repeating events are more likely to be strengthened

      • Replaying memories (including during sleep) enhances connections between neurons and leads to better memory

      • Arousal may also influence memory formation: The amygdala influences consolidation in the hippocampus and basal ganglia 

 

Flashbulb memories

  • Flashbulb memories: vivid episodic memories for circumstances in which people first learned of a surprising and consequential or emotionally arousing event

  • Shocking memories may be persistent because arousal enhances their consolidation

  • Despite their vividness, forgetting of details occurs for flashbulb memories, like with typical memories

 

Blocking

  • Blocking: the temporary inability to remember something

    • the tip-of-the-tongue phenomenon

    • Blocking often occurs because of interference from words that are similar in some way, such as in sound or meaning, and that recur.

Persistence

  • Persistence: the continual recurrence of unwanted memories

  • PTSD is a serious mental health problem, with an estimated prevalence of 7 percent in the United States.

    • The most common triggers of PTSD include events that threaten people or those close to them.

    • Emotional events are associated with amygdala activity, which might underlie the persistence of certain memories.

 

False memories

  • Memories can be distorted, or even implanted, by false information.

    • Imagining an event might lead to confusion of the mental image with a real memory.

    • Children are particularly susceptible to false memories being induced.

      • “lost in the mall” incident

 

Repressed memories

  • The legitimacy of repressed memories continues to be debated by contemporary psychologists, many of whom argue that such memories may be implanted by suggestive techniques, e.g., hypnosis and guided recall.

    • While research shows that some therapeutic techniques seem especially likely to foster false memories, it would be a mistake to dismiss all adult reports of early abuse.