Neuroscience Terms and Definitions

1. Affective Filter

Definition: The affective filter is an emotional state of stress in children during which their brain’s limbic system, particularly the amygdala, becomes hyperactive. In this state of high stress or anxiety, new sensory information is blocked from passing through the amygdala to reach the higher cognitive centers of the brain, thus preventing effective processing, learning, and long-term memory storage.

Classroom Example: A student experiencing test anxiety may find it difficult to focus or retain information during a review session, as the affective filter prevents new learning from being encoded and stored due to emotional overload.

Citation: Krashen, S. D. (1982). *Principles and Practice in Second Language Acquisition*. Pergamon Press.

2. Amygdala

Definition: A pair of almond-shaped nuclei located deep within the temporal lobes, forming part of the limbic system. The amygdala plays a central role in processing emotions, particularly fear and anxiety, and in modulating memory consolidation. When the amygdala senses a threat, its increased activity can act as an “affective filter,” hindering the passage of new sensory information to memory circuits in the cerebral cortex.

Classroom Example: When a teacher creates a safe, predictable, and welcoming classroom environment, students are less likely to feel threatened or anxious, which helps keep the amygdala calm and more receptive to engaging in learning experiences and forming new memories.

Citation: LeDoux, J. E. (1996). *The Emotional Brain: The Mysterious Underpinnings of Emotional Life*. Simon & Schuster.

3. Attention

Definition: The selective focus of cognitive resources on certain stimuli or tasks while actively ignoring others. Attention is a crucial prerequisite for the effective encoding, processing, and subsequent storage of new information into memory systems.

Classroom Example: A teacher uses various strategies like varying vocal tone, incorporating movement, or posing intriguing questions to capture and sustain student attention during a lesson, knowing that sustained attention is vital for information to enter working memory.

Citation: Posner, M. I., & Rothbart, M. K. (2007). Research on attention networks as a model for the integration of psychological science. *Annual Review of Psychology*, *58*, 1–23.

4. Axon

Definition: The long, slender, fiber-like extension of a neuron that transmits electrical impulses away from the neuron’s cell body to other neurons, muscles, or glands. Axons are the primary transmission lines of the nervous system, enabling rapid communication across the brain and body.

Classroom Example: When explaining how the brain sends messages, a teacher uses a large diagram of a neuron, tracing the path of an electrical signal down the axon to illustrate how information travels from one part of the brain to another, or to a muscle for action.

Citation: Purves, D. et al. (2012). *Neuroscience* (5th ed.). Sinauer Associates.

5. Brain Imaging (Neuroimaging)

Definition: A set of non-invasive techniques used to visualize the structure, function, or biochemical status of the living brain. Techniques like Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) scans provide structural details, while functional MRI (fMRI) and Positron-Emission Tomography (PET) visualize brain activity by detecting changes in blood flow or metabolic processes during cognitive tasks.

Classroom Example: During a brain science unit, students explore images from fMRI scans that show which brain regions “light up” when a person is reading, solving a math problem, or listening to music, helping them understand brain specialization.

6. Brain Mapping

Definition: The use of advanced neuroimaging techniques, such as electroencephalography (EEG) or functional MRI over time, to measure and visualize electrical activity or blood flow representing brain activation along neural pathways. Brain mapping allows researchers to track which parts of the brain are active during various stages of information processing, from sensory intake to storage and retrieval, and to associate activation levels with processing intensity.

Classroom Example: A high school biology teacher introduces students to EEG technology by demonstrating how different mental tasks (e.g., quiet reading vs. active problem-solving) can generate distinct brainwave patterns, using visual examples from real brain mapping studies to illustrate neural activity.

7. Central Nervous System (CNS)

Definition: The major control center of the body, composed of the brain and the spinal cord. The CNS integrates information received from all parts of the body, processes it, and coordinates appropriate responses, serving as the primary hub for thought, emotion, and movement.

Classroom Example: In a science class, students build models of the brain and spinal cord using clay or pipe cleaners to better understand the physical components of the central nervous system and how messages are transmitted throughout the body for sensation and action.

Citation: Bear, M. F., Connors, B. W., & Paradiso, M. A. (2016). *Neuroscience: Exploring the brain* (4th ed.). Wolters Kluwer.

8. Cerebellum

Definition: A large, cauliflower-shaped structure located at the back of the brainstem, beneath the cerebral cortex. The cerebellum plays a critical role in coordinating voluntary movements, balance, posture, and motor learning, including fine motor skills and procedural memories (e.g., riding a bike, playing an instrument).

Classroom Example: When students learn to ride bikes in physical education, practice a dance routine, or refine their handwriting, their cerebellum is actively involved in encoding and refining those motor skills through repetition and feedback.

Citation: Manto, M., & Jissendi, P. (2012). Cerebellum: Links between development, developmental disorders and motor learning. *Frontiers in Neuroanatomy*, *6*, 1.

9. Cerebral Cortex

Definition: The outermost, convoluted layer of the cerebral hemispheres, often referred to as gray matter. This highly folded surface is responsible for most conscious activity, including higher-order cognitive functions such as planning, problem-solving, language comprehension and production, perception, decision-making, and voluntary motor control.

Classroom Example: During project-based learning, students activate their cerebral cortex as they plan their project steps, collaborate with peers, engage in critical thinking to solve problems, and use language to express complex ideas and present their findings.

Citation: Kolb, B., & Whishaw, I. Q. (2015). *Fundamentals of Human Neuropsychology* (7th ed.). Worth Publishers.

10. Cognition

Definition: The mental process by which individuals acquire knowledge and understanding through thought, experience, and the senses. It encompasses a wide range of mental processes including attention, memory, perception, language, problem-solving, reasoning, and decision-making, essentially referring to all aspects of thinking and knowing.

Classroom Example: When students analyze a character’s motivations in literature, develop hypotheses in a science experiment, or strategize during a history debate, they are actively engaging in various cognitive processes that underpin their learning and understanding.

Citation: Anderson, J. R. (2010). *Cognitive Psychology and Its Implications* (7th ed.). Worth Publishers.

11. Dendrites

Definition: Branched, tree-like protoplasmic extensions that sprout from the cell bodies of neurons. Dendrites are the primary receivers of electrochemical signals from other neurons, forming synaptic connections. They integrate electrical activity from these incoming signals, which then influences whether an electrical impulse will be generated and passed down the neuron’s axon. The number and complexity of dendrites in cortical neurons increase significantly in response to new learning, experience, and information storage, forming new branches from frequently activated neurons, stimulated by growth factors.

Classroom Example: As students repeatedly practice a musical scale on an instrument, solve various types of math problems, or engage in deep reading, their dendrites in relevant brain regions grow and branch, strengthening those neural pathways and improving the efficiency of long-term memory formation and retrieval.

Citation: Kandel, E. R., Schwartz, J. H., & Jessell, T. M. (2000). *Principles of Neural Science* (4th ed.). McGraw-Hill.

12. Dopamine

Definition: A key neurotransmitter in the brain that plays a crucial role in regulating attention, motivation, pleasure, reward-stimulated learning, and executive functions. Dopamine release from midbrain regions increases in response to novel stimuli, rewards, positive experiences, and unexpected outcomes, reinforcing behaviors and enhancing focus.

Classroom Example: A teacher uses strategies like positive feedback, gamification, novelty in lesson delivery, and opportunities for student choice to trigger dopamine release, which can significantly improve students’ sustained attention, motivation, and engagement in learning tasks.

Citation: Schultz, W. (2002). Getting formal with dopamine and reward. *Neuron*, *36*(2), 241–263.

13. Executive Functions

Definition: A set of higher-level cognitive processes primarily mediated by the prefrontal cortex that enable conscious control over one’s thoughts, emotions, and actions to achieve goals. These functions include planning, organizing, prioritizing, sequencing, working memory, self-monitoring, self-correcting, inhibition, cognitive flexibility, and abstract problem-solving.

Classroom Example: A teacher scaffolds a multi-step research project by providing graphic organizers for planning, modeling time management strategies, and using checklists for self-monitoring, thereby explicitly supporting the development of students’ executive function skills needed for complex academic tasks.

Citation: Diamond, A. (2013). Executive functions. *Annual Review of Psychology*, *64*, 135–168.

14. Glia

Definition: Specialized non-neuronal cells in the nervous system that provide crucial support, nourishment, and protection to neurons, and play active roles in modulating neuronal activity and brain plasticity. Major types include astrocytes (regulating blood flow and neurotransmitters), oligodendrocytes (forming myelin sheath), and microglia (immune defense and inflammation regulation).

Classroom Example: While not a direct K-12 curriculum topic, a high school neuroscience unit could enhance understanding by explaining how glial cells are essential “support staff” for neurons, allowing students to appreciate the complex cellular environment that enables all learning and thinking processes.

Citation: Fields, R. D. (2009). The other half of the brain. *Scientific American*, *300*(4), 54-61.

15. Graphic Organizers

Definition: Visual and spatial diagrams designed to align with the brain’s natural tendency for patterning and making connections. They facilitate the encoding, consolidation, and storage of sensory information by helping learners organize new material into brain-compatible patterns, linking it meaningfully with existing memories and prior knowledge.

Classroom Example: During a nonfiction reading lesson, students use a Venn diagram to compare and contrast two historical figures, or a cause-and-effect chart to organize events, thereby promoting deeper patterning and retention of information in their brains.

Citation: Marzano, R. J., Pickering, D. J., & Pollack, J. E. (2001). *Classroom instruction that works: Research-based strategies for increasing student achievement*. ASCD.

16. Gray Matter

Definition: A major component of the central nervous system, consisting of neuronal cell bodies, dendrites, unmyelinated axons, synapses, and glial cells. It appears darker than white matter due to the absence of extensive myelin sheaths. Gray matter is where most of the brain’s information processing, integration, and analysis occur, including cognitive functions like perception, memory, and decision-making.

Classroom Example: A high school anatomy class uses detailed brain models and diagrams to differentiate between the darker gray matter (where thinking and processing happen) and the lighter white matter (the brain’s communication highways), discussing how each contributes to learning and memory formation.

Citation: Giedd, J. N., & Rapoport, J. L. (2010). Structural MRI of pediatric brain development: What have we learned and where are we going? *Neuron*, *67*(5), 728–734.

17. Hippocampus

Definition: A curved, seahorse-shaped structure located deep within the medial temporal lobe of each cerebral hemisphere, forming a crucial part of the limbic system. The hippocampus plays a major role in the formation of new declarative memories (facts and events), memory consolidation (transferring short-term to long-term memory), and spatial navigation and memory.

Classroom Example: During a field trip to a historical museum, students remember new content better when the teacher actively connects it to previously learned material or asks them to create a mental map of the museum, thereby activating the hippocampus’s role in memory consolidation and spatial memory.

Citation: Squire, L. R., & Zola-Morgan, S. (1991). The medial temporal lobe memory system. *Science*, *253*(5026), 1380–1386.

18. Limbic System

Definition: A complex set of functionally linked brain structures located beneath the cerebral cortex, including the hippocampus, amygdala, thalamus, and hypothalamus. This system is primarily involved in regulating emotions, motivation, memory formation, and processing complex socio-emotional information, playing a key role in how emotional states influence learning.

Classroom Example: A classroom that prioritizes emotional safety, encourages open communication, and incorporates collaborative discussion can positively engage the limbic system, leading to enhanced memory retention, increased motivation, and improved social-emotional well-being among students.

Citation: Rolls, E. T. (2015). Limbic systems for emotion and for memory, but no single limbic system. *Cortex*, *62*, 119–157.

19. Long-Term Memory

Definition: A memory system that stores information over extended periods, ranging from minutes to a lifetime. Long-term memory is formed when information from short-term (working) memory is strengthened through repeated review, active recall, and meaningful association with existing neural patterns and prior knowledge, resulting in durable physical changes in neuronal circuits.

Classroom Example: A teacher helps students retain complex science vocabulary by implementing spaced repetition, encouraging them to create concept maps, and connecting new terms to real-life examples and personal experiences, thereby facilitating the transfer of information into long-term memory.

Citation: Ebbinghaus, H. (1885). *Memory: A contribution to experimental psychology*. Dover Publications.

20. Metacognition

Definition: “Thinking about thinking”; it refers to an individual’s knowledge about their own cognitive processes and the ability to monitor, regulate, and direct their learning and problem-solving strategies. In education, fostering metacognition empowers learners to become more strategic and self-directed.

Classroom Example: After completing a challenging writing assignment, students engage in metacognitive reflection by discussing which planning strategies helped them stay organized, what challenges they encountered, and how they might adjust their approach for future assignments to optimize their learning process.

Citation: Flavell, J. H. (1979). Metacognition and cognitive monitoring: A new area of cognitive–developmental inquiry. *American Psychologist*, *34*(10), 906–911.

21. Myelin

Definition: A fatty, insulating substance that forms a protective sheath around the axons of many neurons in the nervous system. Composed primarily of lipids and proteins, myelin acts like electrical insulation, significantly increasing the speed and efficiency of nerve impulse transmission along axons, ensuring messages are sent rapidly and without loss.

Classroom Example: A teacher explains that repeated, deliberate practice of skills like playing a musical instrument or solving complex math problems strengthens neural pathways, and as a result, myelin wraps more securely around frequently used axons, leading to faster and more automatic processing.

Citation: Fields, R. D. (2008). White matter in learning, cognition and psychiatric disorders. *Trends in Neurosciences*, *31*(7), 361–370.

22. Myelination

Definition: The process of forming the myelin sheath around nerve fibers (axons). This developmental process is crucial for the efficient functioning of the nervous system, as it allows electrical signals to travel more rapidly and reliably along neurons. Myelination continues throughout childhood and adolescence, contributing to cognitive development and skill acquisition.

Classroom Example: Students who consistently practice a specific reading strategy, such as decoding multi-syllabic words, are improving the myelination of the neural circuits involved in reading, which leads to increased reading fluency and automaticity over time.

Citation: Sowell, E. R., Thompson, P. M., Tessner, K. L., & Toga, A. W. (2001). Mapping early brain development: The teenage brain. *Nature Neuroscience*, *4*(7), 743–747.

23. Neuronal Circuits

Definition: Interconnected networks of neurons that communicate with each other through electrochemical signals transmitted across synapses. When specific patterns of activity are repeatedly stimulated within these circuits (e.g., through practice or learning experiences), the efficiency and strength of their synaptic connections are enhanced, leading to more successful encoding, storage, and retrieval of information.

Classroom Example: A student who repeatedly practices spelling a new vocabulary word, or solving a particular type of algebra problem, is strengthening the specific neuronal circuits associated with that information, making it easier to recall and apply that knowledge in the future.

Citation: Bear, M. F., Connors, B. W., & Paradiso, M. A. (2016). *Neuroscience: Exploring the brain* (4th ed.). Wolters Kluwer.

24. Neurons

Definition: The fundamental building blocks of the nervous system, specialized cells responsible for transmitting and processing information throughout the brain, spinal cord, and nerves. Each neuron typically consists of a cell body (soma) containing the nucleus, a single long axon for sending outgoing electrical signals, and multiple branched dendrites for receiving incoming signals from other neurons.

Classroom Example: In a neuroscience unit, a teacher uses visual aids and hands-on activities, such as building neuron models with pipe cleaners and beads, to help students understand the structure of neurons and how these specialized cells communicate to enable all aspects of learning and thought.

Citation: Purves, D. et al. (2012). *Neuroscience* (5th ed.). Sinauer Associates.

25. Neuroplasticity

Definition: The remarkable and lifelong capacity of the brain to change its structure and function in response to experience, learning, environmental stimuli, or injury. This involves the formation of new neural connections (synapses), strengthening or weakening of existing ones, and even the generation of new neurons (neurogenesis), allowing the brain to adapt and reorganize its networks.

Classroom Example: A teacher explains to students that their brains are not fixed but can grow and change through effort and learning, using the concept of neuroplasticity to motivate them to persevere through challenging academic tasks and embrace mistakes as learning opportunities.

Citation: Pascual-Leone, A., Amedi, A., Fregni, F., & Merabet, L. B. (2005). The plastic human brain cortex. *Annual Review of Neuroscience*, *28*, 377–401.

26. Neurotransmitters

Definition: Chemical messengers that transmit signals across a synapse from one neuron to another target cell (neuron, muscle cell, or gland cell). When an electrical impulse reaches the end of an axon, neurotransmitters are released into the synaptic gap, bind to specific receptors on the dendrite of the postsynaptic cell, and either excite or inhibit the activity of that cell, thus propagating or modulating neural signals.

Classroom Example: A teacher uses a visual analogy, like a “chemical key” (neurotransmitter) fitting into a “lock” (receptor) on another cell, to help students understand how neurotransmitters like dopamine or serotonin facilitate communication between neurons and influence mood, attention, and learning.

Citation: Kandel, E. R., Schwartz, J. H., & Jessell, T. M. (2000). *Principles of Neural Science* (4th ed.). McGraw-Hill.

27. Numeracy

Definition: The ability to understand, reason with, and apply numbers and other mathematical concepts in various contexts. It encompasses not just basic arithmetic skills but also the capacity to interpret data, solve quantitative problems, and make informed decisions in everyday life.

Classroom Example: A kindergarten teacher uses hands-on manipulatives, counting songs, and number games to develop early numeracy by helping children connect abstract quantities to concrete objects, symbols, and mathematical vocabulary, building a strong foundation for future math skills.

Citation: Steen, L. A. (2001). *Mathematics and democracy: The case for quantitative literacy*. National Council on Education and the Disciplines.

28. Occipital Lobes (Visual Processing Areas)

Definition: The posterior (rearmost) lobes of the cerebral cortex, primarily responsible for processing visual information received from the eyes. This includes interpreting shapes, colors, motion, and spatial relationships, and integrating these visual inputs to recognize objects, faces, and scenes, connecting them to stored memories and language.

Classroom Example: When students examine complex visual diagrams in a biology textbook, analyze historical photographs, or interpret data presented in a graph, their occipital lobes are highly activated to help them identify patterns, recognize objects, and extract meaning from the visual information.

Citation: Grill-Spector, K., & Malach, R. (2004). The human visual cortex. *Annual Review of Neuroscience*, *27*, 649–677.

29. Oligodendrocytes

Definition: A type of glial cell found in the central nervous system (brain and spinal cord) that specializes in forming the myelin sheath around multiple axons. By wrapping axons in myelin, oligodendrocytes facilitate the rapid and efficient transmission of electrical signals, which is critical for complex cognitive functions and motor control.

Classroom Example: A high school neuroscience class might explore the vital role of oligodendrocytes by discussing how their proper functioning supports fast thinking and coordinated movement, or by examining the impact of demyelinating disorders like multiple sclerosis on neurological function.

Citation: Bradl, M., & Lassmann, H. (2010). Oligodendrocytes: Biology and pathology. *Acta Neuropathologica*, *119*(1), 37–53.

30. Parietal Lobes

Definition: The two lobes of the cerebral cortex located behind the frontal lobes and above the temporal lobes. They are crucial for processing somatosensory information (touch, pain, temperature, pressure), spatial awareness, navigation, and integrating sensory input from various modalities (e.g., visual, auditory, motor) to form a coherent understanding of the world and one’s body in space.

Classroom Example: Students learning to play a musical instrument, typing on a keyboard, or engaging in hands-on science experiments rely heavily on their parietal lobes to coordinate sensory input (e.g., feeling the keys, seeing the screen) with fine motor movements and spatial memory, demonstrating the integration of sensation and action.

Citation: Andersen, R. A. (1997). Multimodal integration for the representation of space in the posterior parietal cortex. *Philosophical Transactions of the Royal Society B*, *352*(1360), 1421–1428.

31. Patterning

Definition: The brain’s fundamental process of perceiving sensory data and organizing it by relating new information with previously learned material, or by chunking material into existing pattern systems. Effective education facilitates this process by presenting new material in ways that highlight relationships, allowing children to generate new neural connections and consolidate information into successful long-term memory patterns for retrieval.

Classroom Example: In a math lesson on multiplication, students use pattern blocks or visual arrays to discover multiples and develop rules based on observed visual patterns, which helps their brains to “pattern” the information more effectively for deeper understanding and retention.

Citation: Sousa, D. A. (2017). *How the brain learns* (5th ed.). Corwin Press.

32. Prediction

Definition: A cognitive process where the brain, having successfully patterned incoming information, uses existing knowledge to anticipate what will come next. This ability is fundamental to learning, problem-solving, reading comprehension, and social interactions. The more accurate and robust the brain’s existing patterns, the more precise its predictions become, forming a powerful problem-solving strategy.

Classroom Example: A teacher pauses during a read-aloud session and asks students to predict what will happen next in the story, encouraging them to use prior knowledge, contextual clues, and character traits to make informed guesses, thereby strengthening their predictive reasoning skills.

Citation: Friston, K. (2010). The free-energy principle: A unified brain theory? *Nature Reviews Neuroscience*, *11*(2), 127–138.

33. Prefrontal Cortex (PFC)

Definition: The most anterior part of the frontal lobes, serving as the brain’s executive control center. The PFC is a hub of neural networks involved in complex cognitive functions, including working memory, planning, decision-making, judgment, emotional regulation, attention focusing, abstract thinking, problem-solving, and linking information to appropriate actions. It allows for the conscious evaluation and manipulation of information to form long-term memories.

Classroom Example: A teacher asks students to evaluate the credibility of different online sources when conducting a research project, requiring them to activate their PFC networks for critical thinking, information evaluation, and conscious decision-making about source reliability.

Citation: Miller, E. K., & Cohen, J. D. (2001). An integrative theory of prefrontal cortex function. *Annual Review of Neuroscience*, *24*, 167–202.

34. Pruning

Definition: A natural and crucial process of synaptic elimination in the brain, where unused or inefficient neural connections (synapses) are selectively removed. This process occurs in waves (e.g., around age three and again in adolescence) and is essential for optimizing brain efficiency, consolidating learning, and strengthening frequently used neural pathways by removing “noise” and allowing remaining synapses to become more robust.

Classroom Example: Educators can support healthy brain development and efficient learning by providing opportunities for students to repeatedly practice and apply key skills and concepts, thereby ensuring that the most relevant neural pathways are reinforced and preserved through the natural process of synaptic pruning.

Citation: Huttenlocher, P. R., & Dabholkar, A. S. (1997). Regional differences in synaptogenesis in human cerebral cortex. *Journal of Comparative Neurology*, *387*(2), 167–178.

35. RAD Learning

Definition: A pedagogical framework emphasizing three key brain systems crucial for optimizing learning: the **R**eticular Activating System (attention/novelty), the **A**mygdala (emotional processing/safety), and **D**opamine (motivation/reward). Activating these systems (also referred to as “Reach and Discover”) through engaging and emotionally relevant experiences can significantly enhance information intake, processing, and memory consolidation.

Classroom Example: A teacher designs lessons that incorporate novelty (e.g., a surprising fact), emotional connection (e.g., personal stories), and opportunities for positive feedback and choice (e.g., gamified activities), all of which activate the RAD system to improve student engagement, focus, and long-term retention.

Citation: Willis, J. (2007). *Research-Based Strategies to Ignite Student Learning*. ASCD.

36. Reticular Activating System (RAS)

Definition: A network of neurons located in the brainstem that plays a crucial role in regulating arousal, sleep-wake transitions, and filtering incoming sensory information. The RAS acts as a gatekeeper for attention, selectively allowing novel, surprising, dangerous, or personally relevant stimuli to reach conscious awareness while filtering out irrelevant background noise.

Classroom Example: A teacher begins class with a surprising fact, a captivating story, a sudden change in activity, or a personally relevant question to immediately engage the RAS and direct student attention toward the topic at hand, ensuring the brain is “ready to learn.”

Citation: Moruzzi, G., & Magoun, H. W. (1949). Brain stem reticular formation and activation of the EEG. *Electroencephalography and Clinical Neurophysiology*, *1*(4), 455–473.

37. Serotonin

Definition: A neurotransmitter that plays a widespread role in the brain, influencing mood, sleep, appetite, digestion, learning, and memory. Imbalances in serotonin levels are associated with conditions like depression and anxiety. Serotonin also promotes dendritic branching, particularly during periods of restorative sleep, which is vital for strengthening neural connections and memory consolidation.

Classroom Example: Teachers who encourage healthy sleep habits, promote physical activity, and foster a positive classroom climate are indirectly supporting optimal serotonin regulation in students, which can enhance their attention, emotional balance, and capacity for learning and memory consolidation.

Citation: Jacobs, B. L., & Azmitia, E. C. (1992). Structure and function of the brain serotonin system. *Physiological Reviews*, *72*(1), 165–229.

38. Short-Term Memory (Working Memory)

Definition: A cognitive system that temporarily holds and manipulates a limited amount of information for immediate use in ongoing cognitive tasks. Information typically remains in working memory for only about 15-30 seconds without rehearsal, and its capacity in mature brains is approximately 7-9 “chunks” of data. It is crucial for reasoning, comprehension, and learning, as it acts as a mental workspace.

Classroom Example: When solving a multi-step math problem, students use their working memory to hold interim calculations and intermediate steps in mind while they proceed to the next part of the equation. Teachers can support working memory by breaking down complex instructions into smaller, manageable chunks.

Citation: Baddeley, A. (1992). Working memory. *Science*, *255*(5044), 556–559.

39. Synapse

Definition: A specialized junction where one neuron (the presynaptic neuron) communicates with another neuron or target cell (the postsynaptic cell) by transmitting electrochemical signals. Neurotransmitters are released from the presynaptic terminal, diffuse across the tiny synaptic gap, and bind to receptors on the postsynaptic membrane, causing a change in its electrical potential and influencing its activity. Synapses are the fundamental sites of information transfer and plasticity in the brain.

Classroom Example: To explain how messages move through the brain, a teacher might simulate a synapse using students: one student (presynaptic neuron) passes a “message” (neurotransmitter) across a small gap to another student (postsynaptic neuron), illustrating the electrochemical communication that underpins all learning and thought.

Citation: Kandel, E. R., Schwartz, J. H., & Jessell, T. M. (2000). *Principles of Neural Science* (4th ed.). McGraw-Hill.