Declarative (Explicit) & Procedural (Implicit) Memory

Boost Your Brain with Mind Lab Pro

Your brain is incredibly complex. Mind Lab Pro has 11 different nootropics all working together to increase your cognition and brainpower to help you live a better life.

If you need to perform at your best, need to focus, problem-solve or maintain a calm and clear mindset, you will get a huge benefit from taking Mind Lab Pro.


  • Better focus
  • Calm mindset
  • 55+ memory and mood
  • Performance focused athletes
  • Student learning


Language is somehow dependent on two different systems of the brain. Humans possess different storage systems known as declarative and procedural memory. Declarative or explicit memory is a subcategory of long-term memory and used for learning facts and events. This type of memory plays a vital role in rapid learning. As the name suggests, this type of memory can be declared. Therefore, these memories can be recalled consciously. 

Remembering your father’s phone number counts into the declarative memory. They are mainly related to the hippocampal region of the brain. 

Declarative MemoryThe procedural memory is quite different from that of the declarative or explicit memory. This implicit memory does not involve the hippocampus. All the memory entails are stored purely into the cerebellum that forms the hindbrain. This is mainly related to the skill development ability of an individual. Remember riding the bicycle for the first time and then bagging up the first position in the cycling race all involve the cerebellum of the brain. Skills like reading, writing, cooking, walking, drive all counts in implicit memory. The memory is composed of automated sensorimotor behavior that is subconsciously driven and we are not typically aware of.  Once learned, these memories automatically do functions that don’t involve our conscious involvement. 

Declarative to Explicit/ Procedural to Implicit

The declarative memory is called explicit memory is based on the concept that we can explicitly store and retrieve this memory in terms of facts and figures. When riding a bike procedural memory will explain to you how to ride a bike while declarative memory will explain your routes through which you need to drive to reach the destination. 

The procedural memories are also called implicit because the previous experiences help in performing a task better without explicit and conscious awareness of previous experiences. Procedural memories are formed when there is a reinforcement of synapses. The procedural memories are the forms of linking connections between the nerve cells. 

Procedural memory is known to form one’s personality as it's closely related to forming one’s habits. In certain memory disorders like Alzheimer's disease, procedural memory is known to function better than the declarative memory. The areas like basal ganglia and cerebellum tend to affect cognitive functions at a greater pace. 

Hence, both the memory types work in integration to form in a complete long-term memory informatics within the sections of the brain. 

Discovery of Implicit and Explicit Memory

Scoville and Milner in 1957 studied a patient named H.M. HM - Henry Gustav Molaison had bilateral medial temporal lobectomy to cure epilepsy. It's explained through the removal of the hippocampus a person is yet able to learn procedural memory. This accounts for separative declarative and procedural memories. After surgery H.M is even known to form memories which are short term, but long-term declarative memories are impeded. 

H.M’s memory impairment was disabling H.M in terms of scenes, words, and manners. He is yet able to acquire other memory perspectives proving the fact that memory is not a single entity and is coordinated in a lot many ways to a certain learning procedure. Declarative memory is what we talk about in day to day terms while non-declarative memory can be explained through performance rather than the recollection. 

Areas of Brain involved in Explicit and Implicit Memory 

The hippocampus plays a vital role in storing declarative memory. It plays its role in early memory storage, the formation of long-term memory and spatial navigation. Although a series of synaptic connections throughout the brain accounts for one’s declarative memory, the hippocampus and its surrounding structures count to be the most important of all. Retaining and recalling episodes of events mainly depends on the functionality of the hippocampus. The declarative within the medial temporal lobe of the brain is consolidated into the temporal cortex. 

The cerebellum having procedural memory forms a major portion of the brain that is mainly involved in monitoring locomotive tasks of an individual. This region of the brain plays an important role in motor control and involves a few cognitive functions like language and attention. 

Subdivisions of Explicit and Implicit Memory 

Explicit memory involves conscious elementary involvement in recording facts and figures. It can be divided into four broad categories:

  • Episodic Memory refers to memory gathered from day to day experiences and can be stated and conjured explicitly. It involves an accident that happened to you while you were traveling in the car. In other words, it is an episodic form of memory remembering the past. 
  • Semantic Memory refers to facts and general knowledge we gather over the years. It is different from episodic memory in general perspective like you know what a car is - its functions, creations, 4-wheeled and more. In other words, it is a factual package.
  • Autobiographical memory refers to episodes of memory collected from one’s life based on a specific object, person, space, and time.
  • Spatial memory refers to the recording of information concerning the spatial arrangement of an individual. It forms a basic cognitive map. We can take an example of your known areas within your vicinity. 

The implicit memory is related to those memory types that involve non-conscious modes of learning not necessarily adding on to your knowledge. It can be further subdivided as follow: 

  • Priming refers to subconscious stimulus creation in response to primary stimulus without guidance and intentions. It can be perceptual, associative, repetitive, positive, negative, affective, semantic, or conceptual. It works best in the same modality stimulus. 
  • Perceptual learning refers to achieving better perception giving rise to discrimination between two similar things. It forms the basis of cognitive processes and plays with a neural basis to bring about the prime effect. 
  • Category learning refers to concept attainment to clarify and categorize different things accordingly. Grouping is the elementary function of this one. It allows a learner to compare different things. Colloquially it implies subjective divisions for better understanding. 
  • Emotional Learning refers to the effect of emotions on an individual. And we all know emotions have a profound effect on an individual. Most of the autobiographical memories tend to carry chunks of emotions into it. 
  • Procedural Learning involves skill attainment for better task attainability at any point in life. It aids the performance of tasks without conscious involvement. 

Memory Process

Several models explain the procedure of how memory gets into your brain store. Few of the models are Atkinson-Shiffrin’s Multi-Store Model of Memory, Baddeley & Hitch’s model of Working Memory, and Craik & Lockhart’s level of processing. 

The Atkinson-Shiffrin’s Multi-Store Model of Memory has three different aspects of memory. These are sensory memory, short term memory, and long-term memory. All three work together to form the basis of this model. Sensory memory involves all the perception taken by different body senses and is further subdivided into three Iconic memory, Echoic memory, and Haptic memory. There is no limit to the amount of sensory information taken in and incorporated. The duration is about 0.3 to 10 seconds. 

If we pay attention to the sensory memory it will be converted to short term memory and if we don’t pay attention, we’ll surely forget the sensory information we perceived. The capacity of short-term memory is roughly 7 with an error of about plus minus two. Its duration is about 10-20 seconds.  

If continuous rehearsal of short-term memory is monitored it will be incorporated into long-term memory. We can carry out rehearsals in two forms. One is maintenance rehearsal and the other is an elaborative rehearsal.  Chunking is the phenomenon of increasing the capacity of short-term memory. The long-term memory has virtually unlimited capacity and duration. This can further be explained through this. We remember things that happened with us quite a few years ago and incorporating new memories to the brain does not require the deletion of already existing stores of memory. 

There’s an infinite space how the long-term memory gets stored in with semantic alterations.

Hippocampus & Memory 

The hippocampus is the main area which works mainly on the explicit memory and has no such role in the implicit memory. Basically, we know that there’s a certain alteration in the implicit memory which lets the memory turn into an explicit one. The new implicit memory to be formed requires an intact hippocampus to get in the new information. These are necessary for the learning and thought processes. Examples include cycling, reading, playing, and a lot more. 

Development of Memory 

The memory is not a single fit in the process. It's a series of coordinated events that go in line to get back to a point of the point where both declarative and non-declarative memories are closely linked. They have different functions and are even characterized by fundamentally different rules of operation. The declarative memory is known to capture and remember a lot many things and when explicit the memory recalling and recognition is one of the elementary functions of the pro. Zola-Morgan says that non-declarative memory is causing the impact of experience most evident via keeping behavioral changes at a greater front. 

Declarative memory can be defined with several adjectives like fast and can support an easily one-learning trial system. Moreover, it being gullible and flexible allows the memory stores to support learning systems and to modify the already existing content. Non-declarative memory can be defined as slow and getting into flow gradually. It's not a prompt attempt and results from incrementation with time.

The declarative memory depends on multicomponent brain connections involving cortical and temporal areas of the brain. While the latter is delivered and spread just to the specified areas. 

Nature of Declarative Memory 

It refers to learning something quickly. This allows different things to develop a near contrast to it. The storage of this memory type within the brain structures is not taut but flexible allowing renewal of certain memories which you no longer like to keep in your stores. The hierarchical orientation of the hippocampus and Para hippocampal areas contributes differently to the formation of different memory types. 

There are certain examples like the perirhinal cortex is responsible for the encoding of objects and the Para hippocampal cortex is responsible for recording major life scenes. These are both known to form an association with that of the hippocampus. Other secondary structures play a major role in declarative memory. These include mammillary nuclei, anterior thalamic nucleus, internal medullary lamina, and mammillothalamic tract. 

Working Memory 

For supportive functions of cognition which includes learning and reasoning encompasses this wide area of working memory. This time of memory replaces the short-term memory. When working memory gets lost or exceeded working memory comes into action. The working memory doesn't show or put on some retention interval. Exceeding a total retention time implies the long-term memory to come into action. 

Nature of Non-declarative Memory 

It is the collection of abilities that can be expressed without legitimate conscious involvement. It broadly contains the motor and perceptual abilities of an individual. These qualities are improved in functionality under the core-hard process of priming. It's good to find that people who are suffering from memory impairment also reflect the ability of priming. 

When considering perceptual learning, it implies one's perception is a response to the stimuli which is achieved. Evaluation is also the basis of non-declarative memory. 

Effects of Brain damage on Memory

  • Damage to hippocampal areas through ischemic changes or stereotaxic lesions. This damage is significantly associated with long term memory impairment. 
  • Damage to the Entorhinal Cortex creates only a mild memory impairment. The entorhinal areas can be further subdivided into perirhinal and Para hippocampal regions. 
  • Damage to surrounding Memory Associated Areas causes delays in simple tasks. It affects the overall involvement of the subdue areas. 
  • Damage to the intertemporal cortex causes impairment in visual perception and recognition memory. It affects long term visual memory formation and alternately new visual memories incorporation into the areas of the brain. 

Relationship between different memory types

Although the mammalian brain is independent in functionality and support. But each of the systems grows and gains control optimistically in achievable terms. Memory systems are defined to work in two different ways which are competitively and cooperatively. Eventually, the loss of one memory system will affect the other ultimately. The main relationship coexists between the hippocampal declarative memory and dorsolateral striatal non-declarative memory. 

Memory implications

Memory forms the fundamentals of one’s life and there’s a great need to keep this framework intact to gain a constant contemporary process of learning and memory. There is a distinctive ability to get through this all by each memory structure as in whole. When considering different clinical conditions, you rather need to follow a few implications of targeted pharmaceutical products. 

As in conditions like phobia, one must target the amygdala which accounts to save habitual memories. In obsessive-compulsive disorders, stratum should be on the target. In diseases associated with forgetfulness like in Alzheimer’s, clinicians will have in point target on to the hippocampal and Para hippocampal areas. 


Declarative and procedural memories are the two types of long-term memories. 

The declarative memory can be stored in terms of facts. On the other hand, procedural memories are related to the experiences that make a person remember skills. 

Declarative memory is based on recall and retrieval while the procedural memory is based on the performance of a person. Procedural memory, unlike declarative memory, also plays a role in defining the personality of a person.

Both these types of memories are stored in different regions of brains by separate processes. They are also affected differently in different memory disorders like Alzheimer’s disease. 

Declarative memory is stored in the temporal lobe while procedural memory is stored in the cerebellum. 

Declarative memory can be subdivided into;

  • Episodic memory
  • Semantic memory
  • Spatial memory 
  • Autobiographical memory

Procedural memory has the following subtypes; 

  • Perceptual learning
  • Category learning
  • Emotional learning 
  • Procedural learning

Several models have been proposed to describe the method by which memories are stored in the brain. 

Damage to different areas of the brain can have impacts on different types of memories. 

Different memory systems interact with one another for their proper functioning. 

Different pharmaceutical products may be used for the treatment of various memory disorders. These products must target the areas of the brain where the memories are stored. 


  1. Ullman, MT (2004). "Contributions of memory circuits to language: the declarative/procedural model". Cognition. 92 (1–2): 231–70. doi:10.1016/j.cognition.2003.10.008PMID 15037131S2CID 14611894.
  2. Tulving E. 1972. Episodic and semantic memory. In Organization of Memory, ed. E Tulving, W Donaldson, pp. 381–403. New York: Academic
  3. Ell, Shawn; Zilioli, Monica (2012), "Categorical Learning", in Seel, Norbert M. (ed.), Encyclopedia of the Sciences of Learning, Springer US, pp. 509–512, doi:10.1007/978-1-4419-1428-6_98ISBN 978-1-4419-1428-6
  4.  Bullemer, P.; Nissen, MJ.; Willingham, D.B. (1989). "On the Development of Procedural Knowledge". Journal of Experimental Psychology: Learning, Memory, and Cognition. 15 (6): 1047–1060. doi:10.1037/0278-7393.15.6.1047.
  5. Squire, L.R. (2004). "Memory systems of the brain: A brief history and current perspective". Neurobiology of Learning and Memory. 82 (3): 171–177. CiteSeerX 15464402.
  6. Oberauer, Klaus (2009). "Chapter 2 Design for a Working Memory"The Psychology of Learning and Motivation (PDF). 51. pp. 45–100. doi:10.1016/s0079-7421(09)51002-xISBN 9780123744890.