Psychology 101 - Week 6: Encoding and Memory Systems
Foundation of Memory and the Three Stages of Processing
Definition of Memory: The nervous system’s ability to obtain and retain information and skills for later retrieval. It is characterized as the learning that persists over time and serves as an internal representation of a past experience.
Complexity vs. Computers: Unlike computers, human memory is imperfect. * The brain is significantly more complicated than a digital storage device. * Perception is unique; individuals process the same information differently based on their specific perceptions and knowledge relevant to themselves. * Memory is subject to failure.
The Three Phases of Memory Conversion: * Encoding: The process of getting information into the memory system. This often involves active listening. * Storage: The process of retaining encoded information over time. This is achieved through repetition or elaboration. * Retrieval: The process of getting information out of storage, primarily through the act of recalling.
Selective Attention and Filter Theory
Selective Attention: The capacity to concentrate on the relevant characteristics of a stimulus while ignoring irrelevant information.
Filter Theory: This theory posits that information not attended to is lost. If an individual is not aware of the information, it is not encoded into the system.
Cocktail Party Phenomenon: A specific psychological effect where a prominent stimulus, such as one's own name or a piece of gossip, can capture attention even when the individual was previously occupied with a different task.
The Atkinson-Shiffrin Model of Memory
Overview: A three-stage model consisting of Sensory Storage, Short-term Storage, and Long-term Storage.
Sensory Storage: * Function: Allows perceptions to appear as unified wholes. * Encoding: Information is experienced through the five senses: visual, auditory, taste, smell, and touch. * Duration: Very brief. Visual (Iconic) is ; Auditory (Echoic) is . * Capacity: Vast, due to the enormous amount of incoming sensory input. * Fate of Information: Unattended information is lost.
Short-term Storage: * Function: Maintains information for immediate use. * Encoding: Primarily auditory, though it can be visual and semantic. Dual coding (using both visual and semantic) provides the richest encoding. * Duration: without manipulation. Working memory manipulation can extend this. * Capacity: Approximately (). Working memory aids in expanding this capacity. * Fate of Information: Information that is not manipulated is lost.
Long-term Storage: * Function: Stores information for access and use at a later time. * Encoding: Primarily semantic, but also involves visual and auditory components. * Duration: Indefinite; probably unlimited. * Capacity: Probably unlimited. * Fate of Information: Some information may be forgotten over time.
Sensory Storage Mechanisms
Definition: Encompasses all information coming from the senses for a very brief duration. * Iconic Memory: Visual sensory memory. * Echoic Memory: Auditory sensory memory.
Experimental Evidence (Partial Report Study): A variant of a study allowed participants to give a partial report, revealing that letters are only maintained in iconic sensory storage for approximately .
Experiential Continuity: Sensory storage allows the world to be experienced as a continuous stream rather than discrete sensations. * Example (Blinking): When we blink, the mind fills in the quarter-second () the eyes are closed so that we do not see black. * Example (Movies): Sensory storage allows us to see moving images in a movie rather than a sequence of static, frame-by-frame pictures.
Short-Term and Working Memory
Short-Term Memory (STM): Described as a buffer or holding place containing a set of "slots" whose values fade away. A small amount of info is encoded and maintained for a short time (e.g., remembering a phone number for only a few seconds).
Working Memory: The active processing component that allows information to remain in the short-term storage for longer durations. * Processes include repeating a phone number or visualizing information.
Miller’s 1956 Digit Span Experiment: Research involving lists of digits that increased by 3 each time.
Chunking: The process of organizing items into familiar, manageable units. This often occurs automatically and aids significantly in memory capacity.
Maintenance Rehearsal: The use of working memory processes to repeat information based on its sound (auditory). This provides only shallow encoding.
Peterson & Peterson’s 1959 Experiment: Demonstrated that performing multiple cognitive tasks simultaneously interferes with chunking and rehearsal. * Procedure: Participants were presented with 3 letters, a 3-digit number, and asterisks (e.g., "ABC", "123", "**"). They had to memorize the 3 letters, then count down by 3s from the number for every asterisk presented, then attempt to write down the original letters.
Serial Position Effect
Primacy Effect: The tendency for people to remember items at the very beginning of a list. These items have usually already been transferred to Long-Term Storage (LTS). On a graph, this is represented by a downward curve following the initial items.
Recency Effect: The tendency for people to remember items at the end of a list because they are still being actively rehearsed in Short-Term Memory (STM). On a graph, this is represented by an upward curve at the end.
Long-Term Storage and Encoding Strategies
Elaborative Rehearsal: Using working memory to think about how new information relates to oneself or prior knowledge. This is a form of semantic processing and provides deeper encoding for more successful long-term storage.
Association Networks: The organizational structure of meaning in LTS. * Spreading Activation Models: Encountered information activates specific "nodes" for memories in LTM. Activating one node increases the likelihood that linked nodes will also activate, making retrieval easier.
Semantics: Regarded as the best way to process and remember new words. This includes understanding the meaning independently or teaching the concept to others.
Dual Coding: A highly successful method using a combination of both visual and semantic encoding.
Schemas: Cognitive structures that aid in perception, organization, and the use of information. * They help construct new memories by filling in gaps within existing memories, interpreting meaning, and overlooking inconsistencies. * Caution: Schemas can lead to biased encoding.
Types of Long-Term Memory (LTM)
Explicit (Declarative) Memory: Memories that represent "knowing that." They consist of facts and experiences that can be consciously recalled and spoken. * Processing: Effortful processing. * Neural Basis: Encoded by the hippocampus and stored in the temporal cortex. * Semantic Memory: Knowledge of facts (e.g., knowing a tomato is a fruit, not a vegetable; describing directions to a friend). * Episodic Memory: Knowledge of personal life events (e.g., remembering getting a present on your birthday).
Implicit (Nondeclarative) Memory: Memories that represent "knowing how." These are memories one may not be aware of and cannot easily speak of. * Processing: Automatic processing. It is so unconscious that consciously thinking about the action can interfere with the behavior's production. * Neural Basis: Encoded by the amygdala (emotional aspects) and the cerebellum (coordination aspects). Stored in the cerebellum. * Duration: Generally lasts for a long time. * Procedural Memory: Motor or muscle memory (e.g., playing the piano; speaking a language learned as a child). * Classically-Conditioned Associations: Emotional responses (e.g., being afraid of the dentist because previous checkups were painful).
Neuroanatomy of Memory
Prefrontal Cortex: Responsible for working memory.
Temporal Lobe: Responsible for explicit memory.
Amygdala: Responsible for implicit and emotional memories.
Cerebellum: Responsible for implicit and procedural memory.
Hippocampus: Responsible for consolidation and spatial memory.
Psychology Review Facts
Mental Lexicon: The term for one's internal collection of words.
Recognition vs. Recall: * Recognition is not the same as recall. * Multiple choice questions test recognition; free response questions also essentially test recognition (Note: Transcript says "Free response = multiple choice" and "multiple choice = recognition").
Continuous Reinforcement: A schedule where a reward is provided every single time a behavior occurs.
Developmental Stages/Moral Rules: * Conventional Level: Based on following rules. * Preconventional Level: Based on rewards and punishments.
Social & Life Data: * Most couples do not report satisfaction during the period they are raising children. * Flashbulb Memories: These memories lose accuracy over time but remain highly vivid to the individual. * Social Learning: This process begins early in infancy.