Executive Functions and Working Memory

Introduction

Executive functions are cognitive skills essential for goal-directed behavior. These include the ability to control our attention, be flexible in our thinking, and set and obtain goals. Diamond (2013) has linked these skills to improved performance in various learning contexts. Executive functions also include the management of working memory. Both memory and executive functions (EF) play critical roles in learning and productivity.

Current models of memory include concepts of short-term memory, working memory, long-term memory, and their various subsystems. These systems interact with executive functions such as attention control, cognitive flexibility, and goal setting. Understanding these processes will help you to learn more effectively and attain your goals more often.

Environmental factors and lifestyle choices also affect cognitive performance, including executive functions. These factors include sleep, nutrition, exercise, stress management, and mindfulness. Employing techniques that enhance working memory capacity, such as chunking information or using mnemonic devices, can facilitate acquiring new skills and knowledge. Developing strong executive functions through targeted exercises or cognitive training can improve the ability to manage time, prioritize tasks, and maintain focus on learning objectives (Klingberg, 2010).

Role of Executive Functions

Executive function (EF) “occupies a central role in neuropsychological theories of behavior control” (McCabe et al., 2010). Executive functions include reasoning, problem-solving, planning, management of working memory, and control of focus. Executive function has a significant impact on social, academic, and financial success as well as self-management, emotional regulation, and mental and physical health. Numerous studies have investigated these effects, such as those described in Diamond (2013).

Our perceptions and memory have more internal, built-in structure than might be assumed without prior knowledge of the underlying evidence. This contradicts the concept of the mind as a tabula rosa or blank slate. Current theories of how our memory and cognition function are based on findings from these experiments and discoveries. A high-level overview of some of the key studies related to memory is the article 10 Influential Memory Theories and Studies in Psychology from Psychologist World.

There is some agreement that there are three core EFs on which the other, higher-level functions are built (Diamond, 2013).

1. Self-control (behavioral inhibition) and interference control (selective attention & cognitive inhibition)
2. Working memory
3. Cognitive flexibility (also called set shifting, mental flexibility, and linked to creativity)

Short-term, long-term, and working memory

Short-term memory acts as a temporary holding space for information, while working memory manipulates and manages this information to support complex cognitive tasks (Baddeley, 2012). Long-term memory is responsible for the encoding, storage, and retrieval of information over extended periods (Atkinson and Shiffrin, 1968). These memory systems are not isolated; they interact to support learning and problem-solving tasks (Cowan, 2017).

Some models distinguish working memory from short-term memory, while others treat them as equivalent terms. When treated as distinct, working memory is only what is being actively used in some conscious mental process, while short-term memory includes things that are not being actively used but are available for recall.

We will present a model that aligns roughly with the most established expert views, keeping in mind that the details vary. A working model is still useful, even if imperfect.

Working Memory Model

The model of working memory we describe here was proposed by cognitive psychologists Baddeley and Hitch initially in 1974 (Baddeley AD, Hitch G., 1974), then updated based on new studies over the years.

The Central Executive

Models of cognition usually include some sort of controlling component that is responsible for managing working memory, focus, and other higher-level functions. “Theories of cognitive control typically include an executive component that is responsible for coordinating goal-directed behavior” (McCabe et al., 2010). This “has been conceptualized in different ways; experimental psychologists typically study the working memory system (Baddeley, 1986), and neuropsychologists typically study the frontal lobe or executive functioning (Fuster, 1997)."

The Central Executive is the controlling component in the model proposed by Baddeley and Hitch in 1974 responsible for coordinating the other processes of memory (Baddeley AD, Hitch G., 1974) and (APA, 2018). It works along with different modalities of temporary (short-term) working memory and systems of perception to coordinate memory, focus, cognition, and storage and retrieval to and from long-term memory.

Visuospatial Sketchpad

The visual-spatial sketchpad is a component of working memory responsible for temporarily storing and manipulating visual and spatial information. It allows us to hold mental images and navigate through physical spaces. Information is only held for a short time, typically a few seconds. It contains information on visual aspects (shape, color, size) and spatial aspects (location, movement). There is evidence that the mechanisms responsible for storing spatial and imagery information are distinct from each other. (Cocchini et al., 2002) as well as from the phonological loop.

Phonological Loop

The phonological loop is a component of working memory that handles auditory information and temporarily stores and rehearses verbal information. It is crucial for remembering spoken words, numbers, and other auditory sequences. When you rehearse a poem your high school English teacher has asked you to memorize out loud or subvocally, this is the part of working memory you are using.

Episodic Buffer

The episodic buffer was added to the model of working memory by Baddeley in a work published in 2000 in Trends in Cognitive Sciences(Baddeley, 2000). He described it as a limited-capacity system that acts as an interface between the other components of working memory. It can combine elements of information from other systems and long-term memory into a coherent episodic representation. The episodic buffer is accessible consciously and explains some phenomena the original model did not address, such as the ability to remember longer passages of prose. This may be related to the effective aspects of mnemonic techniques, which use multimodal story visualizations in a narrative sequence to aid memory.

Chunking

Numerous studies have shown the ability to remember roughly 7 plus or minus 2 distinct items at once in working memory. Chunking is an effect that the number of items does not change with the size of items. It was discussed in “The magical number seven, plus or minus two: Some limits on our capacity for processing information.” (Miller, 1956). Remembering seven different three-digit numbers is roughly the same difficulty as remembering seven one-digit numbers. In a domain where you have significant expertise and a deep understanding, the chunks will be larger than someone without that prior learning. For example, chess masters can remember much more about the positions of chess pieces on the board than amateurs.

Encoding-storage-retrieval

Memory is understood to occur in three distinct but interdependent components or phases: encoding, storage, and retrieval. Problems at any stage can lead to forgetting, misremembering, or false memories. This model was put forth in Melton’s theory of memory (Melton, 1963) and has been influential in cognitive psychology. Research has evolved since 1963 with new research often adding nuances or new sub-processes, but the encoding-storage-retrieval framework remains a fundamental concept in understanding human memory.

1. Encoding is the initial process of converting incoming information into a form that can be stored in memory. This can be in different modalities (visual, auditory, tactile, etc.) and at different processing depths.
2. Storage refers to the retention of encoded information over time. This process involves creating and maintaining a record of the encoded information in the brain. This includes short-term memory, working memory, and long-term memory.
3. Retrieval is the process of accessing and recalling stored information back into conscious awareness. Retrieval is influenced by various factors, including the strength of the initial encoding, the presence of retrieval cues, and the context in which recall occurs.

Depth of encoding

The levels of processing model of memory is a theory that the depth of encoding of memory and length of retention afterward depends on the depth of elaboration the information receives (Craik & Lockhart, 1972) (APA 2018b). For example, using the quadratic formula multiple times versus just rereading it would be a deeper level of processing. A further level would be working through a proof of the formula yourself. This also relates to desirable difficulty, incorporating additional difficulties during learning that may impede short-term learning but are beneficial for long-term learning. (Nelson & Eliasz, 2023).

Modalities of learning

The modality effect is a theory that presenting graphical information visually and related textual information through an auditory mode is more effective than presenting the information only visually, including the text. This engages both auditory and visual channels of information in working memory rather than just the visual channel. Studies of a related concept, the split-attention effect, have shown that diagrams with the text integrated into them are more effective than diagrams with separate text, separated spatially. (Chandler & Sweller 1992).

A meta-analysis of the modality effect concluded that “students who learned from instructional materials using graphics with spoken text outperformed those who learned from a graphics with printed text" (Ginns, 2005).

Procedural vs declarative memory

Long-term memory consists of both explicit, declarative memories, such as the narrative of a story or the knowledge of how the tax system works, and implicit memory, which is used unconsciously and includes procedural memory, such as how to return a tennis serve successfully or tie your shoes.

There is compelling evidence that declarative and procedural memory are distinct neurobiological processes. Amnesiac patients with damage to the hippocampus who cannot form new long-term explicit memories have been able to learn new procedures, such as how to play a new game (Brooks & Bradley, 1976). Some of these studies involved the patient Henry Molaison, known as H.M. who was a patient responsible for numerous contributions to the study of human memory. (Wikipedia Contributors, 2024).

Declarative memory, also known as explicit memory, is divided into episodic memory and semantic memory. Narrative memory consists of narrative stores of linked, sequential events. Semantic memory is what we typically associate with knowledge, such as concepts from high school chemistry about atomic structure and chemical reactions. This distinction was first made by Tulving in 1972.

Modes of Thought

An important differentiation in mental processes that relates to executive, function, and memory are System 1 and System 2. System 1 is the more automatic thought, which uses heuristics and can help you quickly recognize faces, duck when something comes towards you, and make quick intuitive judgments. System 1 is very efficient but tends towards bias. System 2 is used when you put in focused, deliberate effort and think analytically, for example, to work on a new type of mathematics problem. This concept and the implications, details, and related research form the core of the book Thinking Fast and Slow by Daniel Kahneman (2013).

Daniel Kahneman’s explanation of System 1 and System 2 modes of thinking (Kahneman, 2011).

Effects of outside factors

Environmental factors and lifestyle choices play a significant role in cognitive function. Executive functions can be impaired by mental health conditions such as ADHD, ASD, OCD, addiction, anxiety, or depression. Stress, lack of sleep, loneliness, poor nutrition, or lack of exercise can also impair EFs. (Diamond, 2013).

Adequate sleep is essential for memory consolidation and efficient functioning of executive processes (Walker, 2017). Proper nutrition, especially essential nutrients, supports cognitive health and affects memory and executive function performance (Gómez-Pinilla, 2008). Regular exercise has been shown to improve cognitive functions and may enhance neuroplasticity, the brain's ability to reorganize (Erickson et al., 2011). Stress management and mindfulness practices can mitigate the negative effects of stress on cognitive processes and promote a more focused and attentive mind (Tang et al., 2015).

Specific Recommendations

How can we use this information about how our mental systems work to improve our lives and maximize our abilities? Here are specific recommendations for optimizing your executive functions to learn, retain, and use information more effectively.

• Eliminate distractions whenever possible while doing focused work or studying.
  • I find the Pomodoro system together with silencing notifications helpful.
• Make the struggle real (desirable difficulty).
  • Use self-testing, interleaved practice, and spaced retrieval (see Testing Effect).
• Aim for a deeper level of processing.
  • Summarize or rephrase into your own words.
  • Practice problems yourself.
  • Create diagrams, infographics, or mind maps.
  • Do research of your own.
  • Teach new concepts to others.
  • Reflect on what you have learned.
• Leverage modalities of learning
  • Link information together into a narrative (aka the Story Method).
  • Visualize imagery, places, actions, and movement (especially the Method of Loci).
  • Use auditory and verbal rehearsal.
• Support cognitive function with self-care.
  • Use mindfulness techniques like meditation.
  • Exercise regularly.
  • Eat a healthy diet.
  • Practice good sleep hygiene.

Conclusion

Environmental factors significantly affect our executive function and ability to focus, but many of these factors are at least partially under our control or influence. Prioritizing your mental and physical health is one of the key parts of increasing your ability to focus and learn effectively. As always, it is important to use techniques that use visual and spatial recall in addition to written or verbal language. Though this article primarily addressed other topics, it is still essential to use self-testing and other means of desirable difficulty to improve recall.

Further Reading

If you find these topics interesting or helpful and want to learn more, read the article How Memory Works | Derek Bok Center, Harvard University (How Memory Works, n.d.) for a good introduction to high-level concepts related to memory and learning based on research. To learn more about working memory, Baddeley himself has a review paper that is available for free online at Working Memory: Theories, Models, and Controversies | Annual Reviews (Baddeley, Alan. 2012). And there are other related articles on memory techniques and concepts at https://www.learnedmemory.com.

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