Chapter 7: Memory. Memory

Transcription

1 Chapter 7: Memory Case Study: H.M. and His Missing Memories Section 1: Memory Classifications and Processes Section 2: Three Stages of Memory Section 3: Forgetting and Memory Improvement Experiment: Applying What You ve Learned

2 Case Study: H.M. and His Missing Memories Brain surgery that cured H.M. of seizures left him with severe memory loss. Cause for the Surgery H.M. underwent brain surgery to reduce epileptic seizures. Temporal lobe surgery is now rare. Today we know that the temporal lobe has an important function in memory, speech, and hearing. Results of the Surgery H.M. was unable to transfer information from his short-term memory to his long-term memory. His ability to remember nonverbal information was severely impaired.

3 Section 1 at a Glance Memory Classifications and Processes Memory can be classed as explicit or implicit. Two main types of explicit memory are episodic and semantic. Memory of sensory input involves three distinct functions: encoding, storage, and retrieval. Main Idea Memory is the process of encoding, storing, and retrieving information. Memory includes factual and general information, experiences of events, and skills.

4 How did a small cake and a cup of tea elicit memories of a garden?

5 Three Kinds of Memory Memory is the process by which we recollect prior experiences and information and skills learned in the past. There are three different kinds of memory. Episodic Memory Episodic memory is memory of a specific event. A flashbulb memory is a memory of an important and intense event. Examples of flashbulb memory: the memory of the terrorist attacks of 9/11 and the assassination of John F. Kennedy. Semantic Memory Semantic memory is the memory of facts, words, and concepts. Episodic and semantic memories are both examples of explicit memory, which is a memory of specific information.

6 Implicit Memory Implicit memory is memory of things that are implied, or not clearly stated. Implicit memory includes practiced skills and learned habits. Skills learned often stay with people for a lifetime, even if they do not use them very often.

7 Encoding The translation of information into a form in which it can be used is called encoding. Encoding is the first stage of processing information. Visual and Acoustic Codes One type of code is visual. People use visual codes when they form a mental picture. Another type of code is acoustic. People use acoustic codes when they use sound. Semantic Codes Another type of code is semantic. A semantic code represents information in terms of its meaning.

8 Storage Storage is the maintenance of encoded information. It is the second process of memory. Maintenance Rehearsal Mechanical or rote repetition of information in order to keep from forgetting it is called maintenance rehearsal. The more time spent on it, the longer the information will be remembered. It does not connect information to past learning and is therefore a poor way to put information in permanent storage. Elaborative Rehearsal A more effective way to remember new information is to relate it to information you already know. This method is called elaborative rehearsal. It is widely used in education.

9 Organizational Systems Stored memories become organized and arranged in the mind for future use. In some ways, the mind is like a storehouse of files and file cabinets in which you store what you learn and what you need to remember. Your memory organizes information into classes according to common features. Filing Errors Our ability to remember is subject to error. Errors can occur because we file information incorrectly.

10 Retrieval Retrieval consists of locating stored information and returning it to conscious thought. Retrieval is the third stage of processing information. Context-Dependent Memory Context-dependent memories are information that is more easily retrieved in the context or situation in which it was encoded and stored. Such memories are dependent on the place where they were encoded and stored. State-Dependent Memory Memories that are retrieved because the mood in which they were originally encoded is recreated are called statedependent memories. Memory is better when people are in the same mood as when the information was acquired.

11 On the Tip of the Tongue Trying to retrieve memories that are not very well organized or are incomplete can be highly frustrating. Sometimes we are so close to retrieving the information that it seems as though the information is on the tip of the tongue. Psychologists call this phenomenon the feeling-of-knowing experience.

12 Current Research in Psychology Unreliable Memories, Unreliable Witnesses Misleading details can be planted into a person s memory for an event that actually occurred. It is also possible to plant entirely false memories, according to Elizabeth Loftus and Daniel Bernstein (Bernstein et al., 2005). Loftus has shown that false memories exist and also that feeling sure about a memory does not prove the memory is a reliable one. One factor in false memory is source confusion. Psychological research is helping train police investigators to avoid using interviewing techniques that can mislead witnesses. One example is pressing for more additional details when a witness has already expressed uncertainty. If a person has a gist trace of a memory rather than a verbatim trace, the memory is likely to be false or inaccurate.

13 Section 2 at a Glance Three Stages of Memory In sensory memory, each of the senses records its input in a distinct register. Sense data that receive attention are retained in shortterm memory. Information from short-term memory can be stored in long-term memory if it is encoded and linked to other stored information. Information can be quickly retrieved from long-term memory because long-term memory is structured, or organized.

14 Three Stages of Memory Main Idea The three stages of memory storage are sensory input, short-term or working memory, and long-term memory.

15 How could roses affect one's ability to remember facts?

16 Sensory Memory Sensory memory is the first stage of information storage. It consists of the immediate, initial recording of data that enter through the senses. Psychologists believe that each of the five senses has a register. Mental pictures we form of visual stimuli are called icons, which are held in a sensory register called iconic memory. Iconic memories are very brief. The rare ability to remember visual stimuli over long periods of time is called eidetic imagery. Mental traces of sounds are held in a mental sensory register called echoic memory.

17 Short-Term Memory Also called working memory, short-term memory is memory that holds information briefly before it is either stored in long-term memory or is forgotten. The Primacy and Recency Effects The primacy effect is the tendency to recall the initial item or items in a series. The tendency to recall the last item or items in a series is called the recency effect. There is no definitive explanation of the primacy effect or the recency effect. Chunking The organization of items into familiar or manageable units is called chunking. Psychologist George Miller found that the average person s short-term memory can hold a list of seven items.

18 Interference Interference occurs when new information appears in short-term memory and takes the place of what was already there. Short-term memory is a temporary solution to the problem of remembering information. It is the bridge between sensory memory and long-term memory.

19 Long-Term Memory Long-term memory is the third and final stage of information storage. It is the stage of memory capable of large and relatively permanent storage. Memory as Reconstruction Memories are not recorded and played back like videos or movies. They are reconstructed from our experiences. We shape memories according to the personal and individual ways in which we view the world. We tend to remember things in accordance with our beliefs and needs. Schemas Schemas are the mental representations that we form of the world by organizing bits of information into knowledge. Schemas influence the ways we perceive things and the ways our memories store what we perceive.

20 Capacity of Memory Psychologists have not yet discovered a limit to how much can be stored in a person s long-term memory. We do not store all of our experiences permanently. Our memory is limited by the amount of attention we pay to things. The memories we store in long-term memory are the incidents and experiences that have the greatest impact on us.

21 Section 3 at a Glance Forgetting and Memory Improvement The three basic remembering tasks are recognition, recall, and relearning. Much of what we think of as remembering actually involves reconstructing ideas based on associations. Forgetting, or memory failure, can be caused by a malfunction in encoding, storage, or retrieval. Forgetting can occur at any stage of memory. Knowledge of how remembering and forgetting occur has led to practical techniques for improving memory.

22 Forgetting and Memory Improvement Main Idea The three tasks of remembering are recognition, recall, and relearning. Failure of any of these results in forgetting.

23 What memories make the greatest impression?

24 Forgetting Forgetting can occur at any one of the three stages of memory. Information encoded in sensory memory decays almost immediately unless it is transferred into short-term memory. Short-term memory will disappear after only 10 to 12 seconds unless it is transferred into long-term memory. Information stored in short-term memory is lost when it is displaced by new information. The most familiar and significant cases of forgetting involve the inability to use information in long-term memory.

25 Basic Memory Tasks Recognition Recognition is one of the three basic memory tasks and involves identifying objects or events that have been encountered before. It is the easiest of the memory tasks. Recall Recall is the second memory task and involves bringing something back to mind. In recall, you do not immediately recognize something you have come across before. You have to search for it and possibly reconstruct it in your mind.

26 Relearning The third basic memory task is relearning. Relearning involves learning something a second time, usually in less time than it was originally learned.

27 Different Kinds of Forgetting Much forgetting is due to interference or decay. Interference occurs when new information takes the place of what has been placed in memory. Decay is the fading away of a memory over time. Both are part of normal forgetting. There are more extreme kinds of forgetting. Repression Freud says we sometimes forget things on purpose without knowing it because some memories are painful and unpleasant. He called this kind of forgetting repression. Amnesia Amnesia is severe memory loss, which is often caused by trauma to the brain. People with retrograde amnesia forget the period leading up to a traumatic event. Memory loss of events after trauma is called anterograde amnesia.

28 Infantile Amnesia Retrograde amnesia and anterograde amnesia are extreme and rare. One type of amnesia that everyone experiences is infantile amnesia, which is the forgetting of events before the age of three. Infantile amnesia is based on biological and cognitive factors.

29 Improving Memory Drill and Practice Drill and practice, or repetition, is one way to remember information. It is an effective way to transfer information from sensory memory to short-term memory and from short-term memory to long-term memory. Form Unusual Associations Memory can be enhanced by forming unusual associations. Relate to Existing Knowledge Elaborative rehearsal relating new information to what you already know is another way to improve memory. Use Mnemonic Devices Mnemonic devices combine chunks of information into a catchy or easily recognizable format.