The Working Memory
The working memory hippocampus loop provides a mental workspace, protected from distraction and emotional reactivity, which enables the mind to make quick and considered decisions and action plans. This loop supports the construction or manipulation of visual images and the temporary storage of current information, such as a recalled seven digit telephone number.
This article presents an original view, based on a new hypothesis, presented in this website, that human memory is stored as memories for combinatorial patterns in nerve cells. The firing of trillions of such patterns by nerve cells support mental activities and the recall of remembered mental functions. For remembered activities, the nerve cells are recalling combinatorial memories stored within nerve cells.
When a person rides a bike, her motor systems recall procedural memories. A person, who recalls a past event uses his episodic memory. A person who recalls a number during calculation uses his working memory. Such events are triggered to meet the objectives of the executive regions in the prefrontal cortex (PFC). The PFC dispatches a combinatorial pattern of nerve impulses to express the will of the individual as desiring a specific objective.The relevant regions recognize the combinations and respond to this request.
- The sensory data concerning images
manipulated in the mind are made continually available by the hippocampus for processing
through recirculating loops.
- This website suggests that generic
knowledge, domain knowledge and episodic memories are processed as
combinatorial patterns by the hippocampus.
- The prefrontal regions manage
- The basal ganglia manages preprogrammed
sequences of images to combine one image with another to create a new
- The PFC was noted to be active, while
sensory information was temporarily unavailable.
- Recent experiments have linked the
hippocampus to the maintenance of working memory.
- Baddeley and Hitch suggest the presence
of slave systems, which manipulate data in working memory.
- Others argue that data manipulation
also uses long term memory.
Working Memory – Hippocampus –PFC And The
Recognizing the neural instructions from PFC,
the basal ganglia initiates pattern recognition sequences (such as
the manipulation of images), which help to meet the request. The
system wide data concerning the manipulation process is continuously
articulated and refreshed in a loop circuit to the prefrontal regions
by the hippocampus. The availability of such data, after the sensory
inputs cease to be available, through the recirculating loops of the
hippocampus enables the decision making processes of PFC. The
hippocampus subsequently assists the recording of such sequences of
neural firing patterns as long term episodic memories in extensive
regions of the cortex.
Working Memory – Hippocampus –
This website suggests that intuitive
recognition of combinatorial patterns enables the mind to respond in
context by identifying patterns stored in a vast memory. Such
memories were discovered to be applied for hundreds of millions of
years by the olfactory sense (Nobel Prize 2004) for the instant
identification of odors. Complex intelligence depends on the
memories of nerve cells for dendritic firing combinations for signals
from numerous pattern sensing regions. This website suggests that a
neuron fires, when it recognizes a combinatorial pattern in the array
of its receiving dendrites. The pattern may be a single signal in the
array, signals in a channel in the array, or a specific combinatorial
pattern of signals in the array.
This website suggests that
implicit memory for an odor is assembled, when nerve cells routinely
record the related firing combinations.
Such memories are further consolidated through LTP, neural
plasticity, or neuronal reverberation. Such memories
are represented as
arrays of combinatorial patterns in hierarchies of recognition
regions, which recognize objects and events based on sensory inputs.
This website suggests that episodic memories can be represented in
the system as arrays of combinatorial codes.
firing of a single neuron in recognition of a complex concept implies
that it is one element of an array, which represents a specific
category of thought. It has been discovered that individual neurons
fire consistently on recognition of such a subtle concept as
“Clinton.” The neuron was reported to respond for varied photos
and even references to “The President.” Thus the combinatorial
reference structures in the hippocampus may be able to access the
length and breadth of human thought as generic knowledge, domain
knowledge and episodic memories. Recalled patterns representing
objects and events (episodes) and their links enable the complex
decision making processes of the PFC.
Memory – Hippocampus –The Basal Ganglia & Attention
basal ganglia developed as a convergent cortically re-entrant loop
along with the development and expansion of the cortical mantle in
all species of vertebrates. A major skill of the organ was to enable
the PFC to focus attention on any part of the body. Maunsell studied
neural signals in the visual area of the cortex of monkeys, when
viewing a swarm of dots on a computer screen. In this cortical
region, specific neurons fired for specific dots.
animal focused on just one of the dots, the directed attention caused
the neurons that signaled its motion to respond more strongly. At the
same time, neural signals related to other dots were attenuated or
filtered out. Under instructions from the PFC, the basal ganglia
dispatches the impulses, which are recognized by the observed area,
which responds with increased neural activity, while the neighboring
neurons became inhibited. Paying attention to your toe makes your
PFC become aware of the pressure of your shoe on it.
Working Memory –The Basal
Ganglia Processes Thoughts
manipulation of an image is achieved through a sequence of thoughts.
Ann Graybiel recorded neural activity in the basal ganglia of a
monkey, while it learned to associate the sound of a click with the
availability of a sip of juice. A sip of juice is achieved by the
animal through a sequence of muscle movements. With the start of
activity in the throughput lines of the region, “spidery arms that
eavesdropped” on the flow fired in rhythm, and learned the sequence
of movements. Graybiel noted that, later, the expression of the
objective by the PFC (or by emotions) caused the basal ganglia to
mirror the firing rhythms, converting it into an act.
television set recognizes the selected movie channel (the drive
objective) and delivers a preprogrammed set of images, which enact
your movie. The basal ganglia carry a galactic store of
preprogrammed habitual actions, finely tuned to meet specified
objectives. The manipulation of an image within the mind is such an
objective. The basal ganglia selects the appropriate sequences of
thoughts, which combine one image with another to enable you to
visualize a man with the head of a horse. The prefrontal regions set
objectives and the basal ganglia act to achieve those
Memory – Hippocampus -Working Memory Activity
the electrical activity of neurons in the PFC of monkeys while they
were doing a delayed matching task. In that task, the monkey observed
a bit of food being placed under one of two identical looking cups. A
shutter was then lowered for a variable delay period, screening off
the cups from the monkey's view. When the shutter opened, the monkey
was allowed to retrieve the food. Successful retrieval required
holding the location of the food in working memory over the delay
Fuster found neurons in the PFC that fired mostly
during the delay period, suggesting that such firing represented the
food location while it was invisible. Later research also showed such
the posterior parietal cortex, the thalamus, the caudate, and the
globus pallidus. The persistence of the image in the prefrontal
regions, while the shutter was closed follows post-perceptual
processing in the absence of sensory stimulation. This article
suggests that the hippocampus has mechanisms, which can stimulate
such activity. This is part of the brain's process of encoding and
binding experiences into cohesive units and registering it into
Working Memory –
Hippocampus –Data Manipulation In Memory
and time book marks enable the mind to recall specific images to
manipulate them. The hippocampus uses eye movement and head
direction data as an inertial compass to chart geographic movement
and position. Visual and sound information triangulate the location.
These eye and ear coordinates are mapped by head direction cells,
grid cells, and border cells in the entorhinal cortex and the closely
linked hippocampus. The tactile, gustatory, olfactory, spatial, and
motor activities produced by the free exploration of novel objects
trigger precise contextual combinatorial links in multiple brain
Attention is the process which dramatically
increases neural activity. After a novel experience for an animal in
a cage, the correlation of neuronal reverberation between groups of
cells increases markedly, continuing for several hours after the
learning experience. When these active groups of neurons fire in
rhythm, among millions of silent ones, they store combinatorial
memories. Over many sleep/wake cycles, the hippocampus spreads
associative learning to extensive regions of the nervous system.
These same mechanisms enable the organ to sustain the current
thoughts in circulation, to enable the PFC to manipulate
Working Memory –
Hippocampus –Maintenance of Memory
experiments by Ben-Yakov and Dudai (2011) also link the hippocampus
to the maintenance of working memory. In this case, a “stimulus
offset” has been reported, where events become “time locked,”
after perception, in the absence of sensory stimulation. In
their (fMRI) experiments, they identified bilateral hippocampus
activity starting immediately after stimulus presentation.
processing in the absence of sensory stimulation was time-locked
to the offset
of sensory input. The activation was found to increase for
subsequently remembered over forgotten content. Such post-stimulus
activity may be encoding and binding experiences into cohesive units
and registering it into memory. Working memory maintenance may be
part of the long term memory maintenance process by the hippocampus.
This is achieved by periodical replay of information in the
hippocampus with a rhythmic activity.
Memory – Hippocampus - Baddely & Hitch Model
multicomponent model of working memory proposed by Baddeley
and Hitch suggests a central executive, which is responsible
for directing attention to relevant information, while suppressing
irrelevant information and inappropriate actions.
The executive coordinates mental activity, to complete more than one
task at the same time. The central executive has two "slave
systems." One processes phonological information (the sounds of
language), preventing its decay by continuously articulating its
contents, thereby refreshing the information.
slave system remembers a seven-digit telephone number as long as it
is repeated. The other “slave system” manipulates visual and
spatial information, which deal with shape, color, texture and
location. Later this model added an episodic buffer, which
temporarily maintains episodic memories. This article suggests that
all processes of the mind can be shown to be achieved through pattern
recognition of contextual memories. The process can be shown to have
the capability to recognize a pair of scissors by touch, or the
capability for riding a bicycle. The PFC, the basal ganglia and the
hippocampus perform these functions, utilizing the numerous special
purpose recognition regions of the brain.
Memory – Hippocampus -Ericsson & Kintsch Model
and Kintsch argued that the seven chunks of information available to
working memory is inadequate to understand the complex relations
between thoughts expressed in a novel or a paragraph of scientific
text. Ericsson and Kintsch suggest that the mind accomplishes this
by storing most of what we read in long-term memory, linking them
together through retrieval structures. We need to hold only a few
concepts in working memory, which serve as cues to retrieve
everything associated to them by the retrieval structures.
main role of the hippocampus is to enable an animal to find its way
to a hidden source of food. This website suggests that to enable the
food caching ability of animals, the hippocampus may store the last
known status of available knowledge. Thus, when we read a novel, or
experience a new situation, each sentence, or new insight may be only
updating the most recent information. The ability to remember the
contents of a sentence may be adequate to add the new understanding
to this massive current database of episodic memories. Much
information overload may be avoided with the capacity of the mind to
remember the last perceived state of any situation. The mind has a
remarkable capacity to pick up from the last viewed position of a
book, or even a movie.
The hippocampus may store links to
the last viewed status of a hero, or the current stage of a design
solution. The information in a sentence may be adequate for us to
comprehend a new concept. As in the Ericsson and Kintsch model, the
content of working memory as well as the understanding of sentences
may only require the same time interval in the working memory for
post-perceptual processing in the absence of sensory stimulation.
This page was last updated on 08.10.2018.
This page was last updated on 08.10.2018.