Evolution of the Model – Even though the standard model provides a basic foundation for thinking about memory, in the last decade it has evolved in two major respects.
- Firstly, the standard model is a serial processing model: it proposes a series of stages of memory that occur one at a time in a particular order. Research has found that a serial processing model cannot provide a full account of memory for two reasons:
- Most sensory information is never consciously (placed in STM) but it can nevertheless be stored and retrieved.
- The process of selecting which sensory memory to store in STM is actually influenced by LTM, that is we can only decide how to filter information from the sensory environment by comparing that information with the information stored in our LTM. In other words, we cannot decide whether sensory information is valuable – and therefore necessary to be placed in short term memory – unless we cross check it with past experiences located in our long term memory.
- And lastly, researchers have come to view memory as involving a set of modules– discrete but interdependent processing units responsible for different kinds of remembering. These modules operate simultaneously rather than serially. For example:
- Say you were to simultaneously hear thunder and see lightning, you would identify the sound using auditory modules in your temporal cortex, and you would identify the image as lightning using visual modules in your occipital and lower temporal lobes, and pinpoint the location of the lightning using a visual-spatial processing module that runs from the occipital lobes through the upper temporal and parietal lobes. When you remember this episode (the lightning/thunder that is), all three modules will be activated at the same time and you will have no awareness that these memory systems have been operating in parallel.
Working Memory – Because people use STM as a ‘workbench’ to process new information and to call up relevant information from LTM, many psychologists now refer to STM as working memory – the temporary storage and processing of information that can be used for problem solving and various other mental tasks.
- Information stays in working memory only as long as the person is consciously processing, examining or manipulating it.
- Like the older concept of STM, working memory includes both a temporary memory store and a set of processes designed for mentally manipulating information temporarily held in that store.
- Recent research suggests that working memory contains three memory systems: a visual memory store, a verbal memory store, and a central executive that controls and tweaks the information contained in these two stores.
Central Executive – Processes such as rehearsal, reasoning and making decisions about how to balance two tasks simultaneously are the work of a central executive system that has its own limited capacity, independent of the information it is storing or holding momentarily in mind. Visual Memory Store – The visual memory store, also called the visuospatial sketchpad is a temporary image that a person can hold in the mind for roughly 20-30 seconds. It temporarily stores visual information such as the name and location of objects in the environment, so that, for example, a person could get a bottle of milk from the fridge, and remember where their bowl of cereal was left on the table. Images in the visual store can also be mentally rotated and moved around. Verbal Memory Store – Within the verbal memory store, words are stored in order, based primarily on their sound rather than their meaning. Researchers have found that a list of similar sounding words (such as man, cap, map and pat) are more difficult to recall than a list of words that do not sound alike. Declarative and Procedural Memory – There are two kinds of information that people generally store, they are declarative and procedural memories. Declarative memory is any factual information that can be stated or ‘declared’, such as your age or your address. Procedural memory is any procedural knowledge or skills, anything that we know how to do, such as playing the guitar or typing on a computer keyboard. Declarative memory can be generic or episodic. Generic memory refers to general world knolwedge or facts, while episodic memory consists of memories of particular events. Explicit Memory – Explicit memory Involves the conscious retrieval of information. There are two types of explicit retrieval: recall and recognition.
- Recall is the spontaneous conscious recollection of information from LTM, this is the memory retrieval that occurs when two friends talk about ‘old times’ for example. Although recall occurs spontaneously, it still requires conscious effort to dig up from LTM. If you don’t have the right cues to signal recall then you will experience what is known as the tip of the tongue phenomenon, which is when you know the information is somewhere in your brain, only you can’t retrieve it.
- Recognition is the recollection that something currently perceived has been previously encountered or learned. For example, when you answer multiple choice questions on an exam you are using recognition to retrieve information from your long term memory, as you only have to judge the correct answer out of a selection of answers. On the other hand, an essay question only prompts recall from long term memory, as you are required to write the essay yourself and remember the information to write the essay with limited information (the essay question).
Implicit Memory – Implicit memory involves memory expressed in behaviour, it is seen in physical skills and in associative memory learned through conditioning, such as avoiding certain activities that cause distress. Implicit associative memory emerges in experiments on priming effects, in which prior exposure to a stimulus facilitates or inhibits the processing of new information. Past, Present and Future Memory – Everyday memory refers to memory as it occurs in daily life. Everyday memory is functional, focused on remembering information that is meaningful. Retrospective memory is memory for things that have occured in the past, while prospective memory is memory for things that need to be done or accomplished in the future. Next Page