Memory & Perception

Tip-of-the-Tongue (TOT) Phenomenon:

A temporary inability to retrieve a word or name from memory despite feeling that the information is “just out of reach.” It reflects a breakdown in retrieval rather than encoding or storage, indicating that partial memory traces may be activated without full access to the complete item.

Encoding:

The set of mental operations that transform sensory input into a form the brain can store and later retrieve. Encoding varies in depth (structural → phonemic → semantic) and quality (imagery, elaboration), which strongly determines how durable the memory will be.

Storage:

The retention of encoded information over time through the stabilization of neural traces. Storage occurs in multiple systems (sensory → short-term → long-term) and varies in capacity, duration, and the format in which information is represented.

Retrieval:

The process of accessing stored information and bringing it into conscious awareness. Retrieval relies heavily on cues, context, and the match between how information was originally encoded and how it is recalled.

Attention:

A selective cognitive process that filters incoming sensory information and determines which stimuli receive mental resources. Attention is necessary for effective encoding, and its limited capacity restricts the amount of information that enters conscious processing.

Filter:

A theoretical mechanism suggesting that attention acts as a gatekeeper, blocking some sensory inputs while allowing others to pass into conscious awareness and working memory based on relevance and importance.

Cocktail Party Phenomenon:

The tendency to automatically detect personally meaningful stimuli (such as your name) in an unattended auditory channel. Demonstrates that some processing occurs outside conscious attention.

Information Processing Theory:

A model describing memory as a series of stages (sensory memory → short-term memory → long-term memory), with information moving between these stages through attention and rehearsal. Emphasizes the flow and transformation of information.

Levels-of-Processing Theory:

A theory proposing that the depth of encoding determines memory retention. Shallow processing focuses on surface features (letters, sounds), whereas deep processing emphasizes meaning and results in stronger, more persistent memories.

Structural Encoding:

A shallow form of processing that focuses on the physical appearance or visual structure of a stimulus (e.g., shape of letters, typeface). Produces weaker memory traces.

Phonemic Encoding:

Intermediate processing that focuses on a stimulus’s sound (e.g., rhyming, pronunciation). Yields better retention than structural but worse than semantic encoding.

Semantic Encoding:

Deep processing of meaning, relationships, and associations. Produces the strongest long-term retention because it connects information to existing knowledge.

Elaboration:

Adding meaningful connections, examples, explanations, or associations during encoding to enrich memory traces. Highly effective for long-term retention because it increases the number of retrieval paths.

Imagery:

Creating mental pictures to represent information. Visual encoding often produces strong memory traces because images are distinctive and involve dual processing (verbal + visual).

Dual-Coding Theory:

Paivio’s theory stating that information encoded both verbally and visually has two distinct memory pathways, making recall more reliable.

Self-Referent Encoding:

Encoding new information by relating it to personal experiences, traits, or relevance. Extremely durable because it ties memory to a well-developed self-schema.

Overlearning:

Continuing rehearsal or study beyond the point of initial mastery. Deepens memory consolidation and significantly reduces future forgetting.

Spacing Effect:

Distributed practice across multiple sessions leads to stronger long-term retention than massed practice (cramming). Works because spacing strengthens consolidation and reduces interference.

Testing Effect:

Retrieving information through practice tests strengthens memory more than further study. Retrieval itself enhances neural consolidation.

Serial-Position Effect:

Improved recall for items at the beginning (primacy effect) and end (recency effect) of a list because of differential rehearsal and varying states of working memory.

Mnemonics:

Structured memory aids (acronyms, loci, rhymes) that improve encoding by imposing meaningful organization on information.

Sensory Memory:

A brief, high-capacity store that maintains exact sensory representations (iconic for vision, echoic for sound) for fractions of a second. Only attended information moves to STM.

Short-Term Memory (STM):

A limited-capacity store (traditionally 7±2 items, though modern estimates are ~4 items) that holds information for 10–20 seconds unless actively rehearsed.

Working Memory:

An active processing system responsible for holding and manipulating information during cognitive tasks like reading, problem-solving, and reasoning. Central to intelligence and learning.

Rehearsal:

The repetition of information to maintain it in STM or facilitate transfer into LTM. Can be maintenance (simple repetition) or elaborative (meaning-based).

Magical Number Seven:

Miller’s classic finding that STM can hold approximately 7 items (plus or minus 2). Modern research suggests capacity may be smaller.

Chunking:

Grouping individual bits of information into larger, meaningful units. Increases effective working memory capacity.

Phonological Loop:

The component of working memory that processes verbal and auditory information. Important for language acquisition and reading.

Visuospatial Sketchpad:

Processes and temporarily stores visual and spatial information, such as mental maps or images.

Central Executive System:

Supervisory control system directing attention, decision-making, and coordination of working memory components. Often associated with executive function.

Episodic Buffer:

Integrates information from the phonological loop, visuospatial sketchpad, and long-term memory into unified episodes or chunks.

Working Memory Capacity:

The individual limit for holding and manipulating information simultaneously. Predicts reasoning ability, academic performance, and susceptibility to distraction.

Long-Term Memory (LTM):

Stores large quantities of information for extended periods, potentially lifelong. Capacity is essentially unlimited, though retrieval depends on cues and organization.

Flashbulb Memory:

Vivid, seemingly detailed recollections of emotionally significant events. Although confidence is high, accuracy is often similar to other memories and subject to distortion.

Decay Theory:

The hypothesis that memory traces fade simply with the passage of time. Not strongly supported for long-term memory, but may apply to sensory memory or unrehearsed STM.

Confabulation:

Filling gaps in memory with fabricated, distorted, or misinterpreted information, often without intent to deceive. Common in certain neurological disorders and everyday memory errors.

Conceptual Hierarchy:

Information organized into multilevel structures ranging from general to specific categories. Helps with recall by providing logical pathways.

Clustering:

The tendency to group related items during recall, reflecting organized long-term memory storage.

Schema:

A cognitive framework or organized knowledge structure that represents concepts, situations, or events. Schemas shape interpretation, encoding, and retrieval and can cause distortions.

Semantic Network:

A model in which concepts are represented as nodes connected by pathways reflecting associations or related meanings.

Spreading Activation:

The process by which activating one node in a semantic network triggers the activation of related nodes, influencing memory retrieval and priming.

Connectionist Model / Parallel Distributed Processing (PDP):

Models suggesting memory is stored in distributed neural networks where knowledge is represented by patterns of activation rather than discrete units. Learning strengthens or changes connection weights.

Retrieval Cues:

Stimuli or hints that help access stored memories by triggering associated pathways.

Context Cues:

Physical, environmental, or situational factors that match the original encoding conditions and facilitate recall.

Misinformation Effect:

A distortion in memory that occurs when misleading information introduced after an event alters the original memory trace, often resulting in false recollections.

Source Amnesia:

Inability to recall the origin of information while retaining the information itself. Leads to confusion about whether a memory is personal, imagined, or externally acquired.

Source Monitoring:

Evaluating where a memory came from—internal thought, personal experience, or external source.

Source Monitoring Error:

A mistake in identifying the origin of a memory, contributing to false memories and distorted recall.

Cryptomnesia:

Unconscious plagiarism—thinking a memory or idea is original when it is actually retrieved from a forgotten source.

Reality Monitoring:

Determining whether a memory is based on external events or internal imagination/thoughts.

Ebbinghaus’ Forgetting Curve:

A predictable pattern showing that forgetting occurs rapidly at first and then levels off. Demonstrates how memory retention declines without rehearsal.

Retention:

The proportion of material remembered, typically measured through recall, recognition, or relearning.

Recall:

A retrieval task requiring generation of information without explicit cues (e.g., essay questions).

Recognition:

A retrieval task involving identification of previously learned information from a set of options (e.g., multiple choice).

Relearning:

Assessing memory by measuring the amount of time or effort saved when learning material again.

Pseudoforgetting:

Forgetting due to ineffective encoding—information was never stored properly, often because of divided attention.

Interference Theory:

The idea that forgetting is primarily caused by competition from other information.

Retroactive Interference:

New information disrupts the recall of previously learned information.

Proactive Interference:

Previous information interferes with learning and recalling new information.

Encoding Specificity Principle:

Memory retrieval is most effective when conditions at retrieval match the conditions present during encoding.

Transfer-Appropriate Processing:

Memory performance is enhanced when the cognitive processes during retrieval match those used during encoding (e.g., semantic vs. phonemic).

Motivated Forgetting:

Intentional or unconscious suppression of memories, often associated with emotional distress.

Repression:

Freudian concept proposing unconscious blocking of anxiety-provoking memories; controversial in contemporary psychology.

Deese-Roediger-McDermott (DRM) Paradigm:

An experimental method showing how lists of related words often produce false recall of a non-presented “theme word,” illustrating how semantic associations create false memories.

Déjà Vu:

The erroneous feeling of having experienced a situation before, possibly due to familiarity without conscious recollection.

Priming:

An implicit memory process in which exposure to a stimulus influences response to a later stimulus, often without awareness.

Mood-Congruent Memory:

The tendency to recall experiences that are consistent with one’s current mood; a component of state-dependent memory.

Long-Term Potentiation (LTP):

A long-lasting increase in synaptic strength resulting from repeated stimulation. Considered a key neural mechanism underlying learning and memory consolidation.

Retrograde Amnesia:

Loss of memories for events that occurred before the onset of amnesia. Typically more severe for recent memories than older ones (temporal gradient).

Anterograde Amnesia:

The inability to form new long-term declarative memories after the onset of amnesia, typically due to hippocampal damage.

Consolidation:

The gradual process through which memories are stabilized in the brain via structural and chemical changes. Occurs partly during sleep and involves hippocampal and cortical interactions.

Declarative Memory:

Memory for factual information and events. Includes semantic (facts) and episodic (personal events) memory. Conscious and explicit.

Nondeclarative / Procedural Memory:

Memory for skills, habits, operations, and conditioned responses. Unconscious and implicit. Resistant to forgetting and often intact in amnesia.

Episodic Memory:

Personal recollections of specific experiences including context, time, and associated emotions. Autobiographical in nature.

Semantic Memory:

General knowledge about the world, including concepts, meanings, and facts independent of personal experience.

Prospective Memory:

Memory for future tasks, such as remembering to take medication or attend an appointment. Sensitive to distraction and multitasking.

Retrospective Memory:

Memory for past events, information, and previously learned material.