Understanding Short-Term and Long-Term Memory: How We Retain What Matters

Memory is a major area of human cognition that allows the human brain to store, retain, and retrieve information necessary for the functioning of the individual human organism in everyday life. Memory could involve anything from holding onto a phone number for a few seconds, to recalling a childhood event decades later, to combining information in all possible ways from these memories.

Underneath all this complexity lies the variance between short-term memory (STM) and long-term memory (LTM). The two are aspects of a person’s cognitive functioning concerning retaining information in a particular way, yet they differ in terms of capacity, duration, mode of encoding, and neural mechanisms. This article elaborates on the distinction between short-term and long-term memory, aiming to relate the functioning of these two systems to human behaviour and learning in general.

What is Memory?

Memory can simply be defined as the process of encoding, storing, and retrieving information. Usually, the memory is divided into three stages: sensory memory, short-term memory, and long-term memory. Sensory memory probably exists for a few tenths of a second before being passed on into short-term memory and on into long-term memory through rehearsal and/or meaningful association.

Read More: Memory 101: Understanding the Basics of Working Memory

Short-Term Memory: Characteristics and Functions 

Data that is temporarily stored for immediate use is referred to as short-term memory. for a limited period of time, usually 15 to 30 seconds. Tasks such as holding a phone number long enough to dial it or following a set of instructions just presented rely heavily on this memory type. The short-term memory categorises several features : 

• Span: Information contained in the short-term memory must last 15-30 seconds; otherwise, decay is expected unless the information is somehow refreshed after this period. 
• Capacity: The famous interpretation given by psychologist George A. Miller in 1956 proposed an average capacity of between 7 ± 2 items through which STMS accept information. Current findings suggest that the actual capacity may be between 4 and 5 items, although this may vary according to the nature of the contents. 
• Encoding: Acoustic encoding is the mostly utilized type of encoding for short-term memory, so that information is typically stored according to how it sounds. That is the reason why people rehearse phone numbers and sometimes even subvocalizes.
• Interference: If there is an interference from interruption, short-term memory can be easily disturbed and often cause forgetting about things that He didn’t encode very deeply or rehearse.
• Rehearsal and Chunking: Short-term memory proves most successful with rehearsal and chunking which are processes in which rehearsal is repetition of information while chunking is breaking information into smaller, discrete meaningful units.

For Example, say you’re given the number 835-4621, and it can easily be memorised in the short term by repeating the digits in your head. But if someone interrupts your rehearsal ever so slightly, the whole number is likely to vanish from your memory, illustrating the fragility of short-term memory. 

Read More: The Psychology of Memory mastery: How to remember everything you learn

Long-term Memory:  Characteristics and Functions 

Unlike STM, long-term memory refers to the retention of information for long periods of time-from hours to an entire lifetime. Long-term memory gives the retention of facts, events, skills, and learned information. The long-term memory categorises several features : 

• Duration: There is no time restrain to long-term memory. Memorable experiences or those things that we repeatedly retrieve tend to stay with us throughout life.
• Capacity: Theoretically, LTM has an unlimited capacity, and therefore, an individual can collect vast amounts of information for their whole lifetime. 
• Encoding: Long-term memory systems use mainly semantic encoding information concerning its meaning. However, episodic and procedural memory can moreover include visual and acoustic encoding.
• Consolidation: Information is stored in LTM after being consolidated, and this process is mediated by sleep, attention and emotional salience. 

Long-Term Memory Types

• Explicit memory (declarative memory)
• Episodic memory (accumulation of personal experiences, events) 
• Semantic memory (accumulation of facts, concepts, knowledge) 
• Implicit (non-declarative) memory
• Procedural Memory (Skills and Tasks) 
• Priming, Conditioning 

For Example, you may forget the phone number you called recently (STM), but you certainly remember your graduation day or the capital of France (LTM).

Difference between STM and LTM 

Read More: Inside the Brain’s Memory Filter: How can we remember what matters the most to us? 

Neural Correlates: How Does the Brain Support Short-Term and Long-Term Memory?

Intensive study has been undertaken into the neurobiological mechanisms of memory. The prefrontal cortex is intensely involved in attention and immediate processing and represents a neural correlate of STM. When you try to solve math problems in your head or try to remember a phone number just given, this particular memory type is related to STM, where manipulation of information is emphasised.

Long-term memories are formed with much greater dependency on the hippocampus, located in the medial temporal lobe, which is vitally involved in the consolidation of declarative memories. Damage to this area, as in patients with amnesia, prevents the formation of new long-term memories, leaving the short-term memory mostly intact. The cerebellum and basal ganglia assist in the brain systems supporting procedural memories (skills and motor learning), while the amygdala, together with another memory system, encodes emotionally charged memories.

Read More: The Psychology Behind Memory Distortion

Transition from STM to LTM

The transition processes from short-term memory to long-term memory require certain conditions to be satisfied. 

• Attention: The concentration of attention improves the efficacy of memory encoding.
• Rehearsal: The repeated impression or practice leads to the gradual entrance of information into long-term memory. 
• Meaningfulness: Information that is meaningful to you personally or emotionally has a greater chance of being retained.
• Sleep: Consolidation of memory is aided by sleep, mainly REM sleep.
• Association: Facilitating the storage of new information in long-term memory by associating it with old knowledge will greatly enhance the process (a technique known as elaborative rehearsal). 

For Example, relating history to one’s life would greatly enhance student recollection over textbook memorisation.

Read More: Psychology of False Memory Syndrome

Working Memory: Bridging the Gap

Some scholars make a distinction between working memory and conventional short-term memory. Working memory, as defined by Baddeley and Hitch back in 1974, is not simply seen as a passive storage place but rather an active system that manipulates and processes information. It consists of a phonological loop, a visuospatial sketchpad, and a central executive, each responsible for processing different sorts of information. This is a workspace in which one uses their mental faculties for planning, problem-solving and understanding language; it is closely related to the short-term memory (STM) but focuses more on executive control and cognitive operations.

Disorders Affecting STM and LTM

Various neurological disorders show the differing nature of STM and LTM.

• Alzheimer’s disease: Early disturbance of short-term memory, later impairment of long-term memory.
• Korsakoff syndrome: Due to chronic alcohol use, it is mainly the inability to form new, long-term memories.
• Traumatic brain injury: Depending on the region affected in the brain, either memory systems may be damaged.
• Transient global amnesia: a rare condition where long-term memories are unaffected but short-term memory is temporarily lost. 

These analyses demonstrate how the short-term and long-term memory systems operate independently and differently.

Read More: Memory Loss and Its Impact on People

Practical Application 

Knowing the distinction between STM and LTM is useful in a variety of fields:

• Education: Rehearsal, chunking, and elaboration can be utilised by educators to assist students in transferring information from STM to LTM.
• Cognitive therapy: Therapists may work on addressing memory distortions by helping clients to reframe long-held (long-term) beliefs. 
• User interface design: Ensuring that interfaces entail a minimum of cognitive load allows users to not exceed the short-term memory capacity.

Conclusion

The short-term and long-term memories are distinguishable systems but interrelated within human cognition. Whereas information can be readily accessed in a small amount through short-term memory, long-term memory provides for a large reservoir of knowledge and experience over long periods. The differences between these two systems—duration, capacity, encoding, and neural basis—speak to the complexity with which we encode and retain information.

Knowing these distinctions is important for understanding the human mind and providing applications in educational, clinical, and technological contexts. The continued research will help deepen our understanding of the complexities of memory and will allow us to develop strategies for enhancing learning, memory retention, and cognitive health.

FAQs

1. What distinguishes long-term memory from short-term memory? 

While long-term memory has an almost infinite capacity and can store knowledge for an indefinite period of time, short-term memory can only store a limited amount of information for a limited period of time (about 15 to 30 seconds). 

2. Does short-term memory give way to long-term memory? 

Indeed, certain information can move from short-term memory to long-term storage through processes including consolidation (often while you’re sleeping), significant associations, and rehearsal. 

3. Which region of the brain controls long-term memory?

The amygdala (emotional memory), cortex, and cerebellum (motor or procedural memory) may be involved in various types of memory, but the hippocampus plays a fundamental role in the encoding and consolidation of long-term memories.

4. Are working memory and short-term memory interchangeable? 

Not really. Working memory is a more active form of short-term memory that actually holds and processes, in real-time, the information, say, to solve a problem or make a decision.

5. Why is it that things can so easily be forgotten from short-term memory?

Short-term memories are particularly vulnerable to interference and decay. Information may overwrite or push out the existing contents almost immediately unless a person continues to rehearse or properly attends to it.