Memory

Objectives

• To give the concept of memory

• To discuss the process of memory

• To understand different problems with the memory

• To learn about memory strategies to improve memory

Lecture Outline

• Concept of Memory

• Three-Stage Model of Memory

• Forgetting and Memory

• Problems with Memory

• Memory Improvement

Memory

• Memory is the ability to code, store and retrieve information– Procedural: how to ride a bike– Factual: definition of “learning”

• Memory involves coding the input of the senses (visual, auditory)

Importance of Memory

• Memory is the most extraordinary phenomenon

• Nearly all higher mental functions (speech, thinking, perceptions, moods, judgments) are based on phenomenon of memory

• Stores events as video recordings along with associated feelings and emotions

• Pleasant and unpleasant memories

Three Stages of Memory

• Human memory resembles a computer• It has three stages:• Encoding: Sensory information is received and

coded or transferred into neural impulses which can be processed further or stored for later use.

• Storage: the encoded information is stored in memory system. Some information is stored briefly and then discarded e.g. telephone number, others used frequently is stored on permanent basis

• Retrieval: when we recall or bring a memory in consciousness, we have retrieved it. This process is called Memory Retrieval.

Three Types of Memory

• Sensory Memory is a brief representation of a stimulus while being processed in the sensory system

• Storage of sensory events such as sights, sounds and tastes

• Short-Term Memory (STM) is working memory– Selective Attention: determine what

information to send to short-term memories – Brief memory, temporary storehouse– Information is stored as images, sounds– Limited capacity (7 items)– Duration is about 30 seconds

• Long-Term Memory

• Permanent storehouse

• LTM is large capacity and long duration

• Information transferred from STM to LTM is coded into categories and stored in terms of meaning and importance

Overview of Memory Model

Varieties of LTM

• Psychologists distinguish between two types of LTM – Semantic memory refers to factual

information, general and specific information (What is the capital of Pakistan?)– Episodic memory refers to memory of

personal events as to where and when an event happened

• “I remember visiting the……………”• “My first day at college”

Overview of LTM

Organization of LTM

• Items in LTM are organized in categories that form a hierarchy with multiple paths (direct and indirect) to each item– Sometimes the cues required to recall an

item are not sufficient – Tip-of the tongue phenomenon: person

can’t easily recall the item, but shows some recall for its characteristics (“…it begins with the letter ….”)

Rehearsal

• This process consists of keeping items of information in the centre of attention by repeating them

• If someone having good memory it is due to his ability and experience in rehearsing

• Not only amount of rehearsal is important but also the ways in which information is rehearsed

• Elaborative rehearsal: giving meaning, organization to the material being rehearsed

Memory Measures

• Recognition is when a specific cue (face or name) is matched against LTM

• Recall is when a general cue is used to search memory• e.g. define the term “personality”

• Relearning refers to a situation in which a person learns material a second time. Memory is evident in savings of time to relearn the second time versus the first

Flashbulb Memories

• Where were you when you first heard:– That Benazir Bhutto had been killed?

Forgetting

• Forgetting is the inability to recall previously learned information

• Forgetting refers to memory failure• Forgetting rate is steep just after learning

and then becomes a gradual loss of recall

Theories of Forgetting

• Interference theory argues that learning new things interferes with what we learned earlier

• Proactive interference: old information interferes with recall of new information

• Retroactive interference: new information interferes with recall of old information

• Decay theory: memory trace fades with time

• Motivated forgetting: involves the loss of painful, unpleasant memories (protective memory loss)

• Repression

• Retrieval failure: the information is still within LTM, but cannot be recalled because the retrieval cue is absent

Interference and Memory

Amnesia

• Amnesia is forgetting produced by brain injury or by trauma– Retrograde amnesia refers to problems

with recall of information prior to a trauma– Anterograde amnesia refers to problems

with recall of information after a trauma

Point of Trauma

Retrograde amnesia Anterograde amnesia

Pathological Changes in Memory

• MMSE

• Amnestic disorders

• Dementias

• Alzheimer’s diseases

Anatomy of Memory

• Two key parts of limbic system are essential in receiving new information and storing it:

• Hippocampus

• Amygdala

Anatomy of Memory

Bilateral damage tothe hippocampus results in anterogradeamnesia

Memory Strategies

• Feedback of Knowledge: feedback allows you to check effectiveness of learning

• Attention

• Recitation and Rehearsal: repetition of what you have learnt

• Organization and Categorization-chunks

• North, man, blue, summer, girl, green, west, yellow, boy, east, woman

• Chunking helps long term memory

• Linking information meaningfully

• Organizing ideas into hierarchies

• Selection: careful and selective marking in your text book

• Attach emotions, feelings: we hardly forget what is emotionally significant

• Distributed practice refers to spacing learning periods in contrast to massed practice in which learning is “crammed” into a single session

• Distributed practice leads to better retention

• Sleep: sleep after the study is helpful and reduces the interference

• Overlearning: memory is greatly improved when study is continued beyond bare mastery.

• Review

• Manage your time

What do we remember?

• Flanagan (1997) argues that we remember:

• 20% of what we read• 30% of what we hear• 40% of what we see• 50% of what we say• 60% of what we do• And• 90% of what we read, hear, see, say and

do.