Limbic System and Memory

Declarative memory is primarily processed through the...

Circuit of Papez

A primary pathway that links together the major limbic system components. -Originally described as part of a collection of structures as involved in _______ affect, it also describes a set structures that when damaged (usually bilaterally) can disrupt ______ processing.

Circuit of Papez Emotional Memory

The amygdala itself also has properties suggesting "learning" or modification with ______

Learning Experience

The ________ is located in the anterior and medial portion of temporal horn under the uncus with which part of it blends. -Uses visceral and somatic sensory inputs to coordinate _____ responses to _______, _____, and visceral stimuli.

Amygdala Emotional Fear, pleasure

______ related memory loss can become evident in cases where general body oxygen levels drop as in heart attacks or cardiac surgery. -_____ trauma and ______ edema can also produce anoxia of this region.

Anoxia Head, cerebral

The Mammillothalamic tract connects the mammillary bodies with the thalamus (______ nuclear group). -This part of the thalamus then sends broad projections (thalamic radiations) to the ______ and other cortical areas associated with the _______ system.

Anterior Cingulate Limbic

______ is important to enhance memory storage, particularly if it is perceived as "significant" for the individual.

Association

Electrical stimulation of the amygdala is _____ and can produce feelings of _____ or _____

Aversive Fear or anxiousness

The most likely substrates for procedural memory are the _____ nuclei loops involved in the performance and integration of _____ tasks.

Basal Motor

Loss of procedural memory is most commonly associated with damage to the __________, prefrontal cortex, parietal cortex, or cerebellum or the pathways connecting them.

Basal nuclei

Procedural memory is processed through cortex- ___________-cortex loops.

Basal nuclie- thalamus

Memory can be significantly affected by association with aspects other than the items being remembered. Priming is an example of an unintended association that can ______- memory.

Bias

As might be suspected by the patterns of brain activation in recall, the substrates for long term memory or its retrieval can be shown to be ____ distributed.

Broadly

______ damage can also interfere with some types of conditioned reflex learning (_____ reflex to a tone and puff of air).

Cerebellar Blink

For working memory, the regions of _______ cortex involved in the memory appear to depend upon the type of task. This can be demonstrated by _______ scan, which can show increases in blood flow with cortical activation during a task

Cerebral Functional MRI

_______ cortex in particular and pathway under it, the cingulum bundle, provide a mechanism for the diffusion of information from Papez's circuit.

Cingulate

Declarative memory loss is generally due to damage of structures associated with the _________. This results in a failure to consolidate memory from ______ term to _______ term memory. Usually ___________ damage is necessary.

Circuit of Papez Short term- long term Bilateral

The process of converting information in working memory to long term memory is ________

Consolidation

These loops have some of the same characteristics of ______ systems (loop, tonic activity, modulation with activity). Changes such as those described for ______ memory may also form the basis of procedural memory through these circuits.

Declarative

______ memory is generally associated with the circuit of Papez

Declarative

______ memory is storage and retrieval that is available to consciousness and can be expressed by language (e.g., remembering a telephone number or images of events that have happened).

Declarative

______ memory: facts, memories of events one can discuss

Declarative

In _______ memory, this is usually demonstrated by exposing subjects to a list of words or objects (without a request to remember them) and then some time later, testing to see if memory of the list has been retained. -Priming is particularly noted for the creation of associational ______ or creating _____ memories.

Declarative Biasing False

The association of random objects, words, or numbers with objects significant to the individual can dramatically increase particularly ______ memory, but also______ aspects.

Declarative or non-declarative

The amygdala and septal area and pathways between them are associated with _________ and ________ behaviors, but also are associated with addition of _________ autonomic components in memories and behaviors. The amygdala has extensive output to the _________ and activation produces feelings of fear or anxiousness.

Defensive and feeding Sympathetic Hypothalamus

The nucleus accumbens, has connections with ________ containing areas of the brainstem and is associated with the _________ nature of behaviors and memories, but also _________ and ___________ behaviors.

Dopamine Rewarding Addicting and OCD

Outgoing connections (efferents) are to the hypothalamus, brainstem and the globus pallidus as part access to the basal nuclei. This suggests the modulation of behavior through _______ reward mechanisms. -Electrical stimulation of this area is ______, and it may be responsible for the for ______ or compulsive behaviors by attaching a positive affect to them.

Endogenous Rewarding Addictive

While the circuit of Papez appears to go in a circle, in fact there are many points at which information _____ and _____ the circuit to include wide areas of cerebral cortex.

Enters and leaves

Only diffuse damage or overactivation (_____, or using ______) will produce appreciable deficits in long term memory.

Epilepsy, electroconvulsive therapy

___________ memories are less sensitive to localized brain damage. Diffuse damage, such as from epilepsy, electroconvulsive therapy, or pathology is usually required.

Established, long term

Its basic connections suggest that a primary function is involved in ______ and ______ behaviors. It receives cortical connections as well.

Feeding and defensive

The normal inability to convert memories from one form to another, loss of memory, or inability to recall is _______ To actually confirm forgetting, it must be clear that a memory has been ______ Forgetting may occur at ______ stage of memory formation.

Forgetting Formed Any

Basic pathway of circuit of papez: extends from parahippocampal gyrus to -hippocampus -mammillary bodies via the _____ -_______ thalamic nuclei -to the ____ gyrus -back to the _____ gyrus via a pathway called the _____ that runs just under the cingulate gyrus

Fornix Anterior Cingulate Parahippocampal Cingulum

Although there are many neural pathways that interconnect the structures of the limbic system, the two major ones are the ______ and _______ tract

Fornix Mammilothalamic

The __________ is particularly sensitive to damage from anoxia and is frequently involved in loss of memory consolidation.

Hippocampus

The consolidation process is particularly sensitive to processes which damage or interfere with the ______ The CA __ area of the hippocampus is particularly sensitive to anoxia (Sommer's sector)

Hippocampus 1

Subcortical components (nuclei) that are primary contributors to limbic system function include:

Hippocampus Amygdala Septal nuclei

Some of working memory is contributed by the ______, however, more recent studies suggest that _____ cortex and other neocortical areas are associated with the more complex tasks of working memory, particularly problem solving and behavioral planning.

Hippocampus Prefrontal

Diseases in which the basal nuclei are damaged (_____ or ______) are typically accompanied by the inability to learn _____ skills (as opposed to performance). _____ affected

Huntington's Parkinson's Motor Dopamine

The fornix- contains two major pathways that interconnect the hippocampus to the septal area, ________, and ________

Hypothalamus Mamillary bodies

_______ memory is the ability to hold ongoing experiences in mind for fractions of a second. It is very large, and each sensory modality (visual, tactile, verbal) appears to have its own register. -It is required to be oriented and responsive in an ______ -Broad areas of ______ cortex and their connections contribute to this.

Immediate Environment Cerebral

Each class of memory can also be divided in time into _________, short term (________) and long term memory.

Immediate Working

Forgetting is the failure to convert one form of memory to another (usually ______ to ______ term)

Immediate or working Long term

Summary: Declarative memory is primarily memory that can be expressed through ______ and is available to _______

Langauge Consciousness

The neural circuitry involved in the incorporation of short term memory to long term memory has been revealed primarily through the study of cases where ______ have produced memory deficits.

Lesions

______ term memory is the more permanent storage of information for periods of days, weeks, months, or years. -The general model studied to identify the incorporation of a piece of information (in the form of afferent action potentials) into a _____ embodiment of neuronal change (engram).

Long term Physical

Damage or disease to either circuitry (usually bilateral) may disrupt _________ formation. The conversion of short term (working) memory to long term memory is ________

Memory Consolidation

Papez's circuit appears to be most closely associated with the formation of ____ memories, primarily of the type that can be stated (______ memory). -In particular, it is associated with the transition between _____ term memory and _____ term memory, aka consolidation of memory

New Declarative Short term and long term

________ (procedural) memory: the first time you rode a bike, know how to ride the bike but not the specific memory of 1st ride

Non-declarative

__________ (procedural) memory - memories that largely cannot be retrieved at a conscious level; how to perform tasks (e.g., riding a bicycle, gymnastic maneuvers).

Nondeclarative

It receives input from the amygdaloid complex, the hippocampal formation, and the substantial nigra and ventral tegmental area (dopaminergic) via the medial forebrain bundle (around the hypothalamus).

Nucleus accumbens

The _______ appears to play a role in addiction though the moderation of the rewarding nature of behavior.

Nucleus accumbens

The _______ lies at the junction of the caudate nucleus and the putamen and next to the septal nuclei; _____ circuitry/_____ valence/pleasure -Contains receptors for a variety of neurotransmitters including...

Nucleus accumbens Reward, positive Endogenous opiods

Amnesia is ______ memory loss. Some of the causes are shown. The inability to form new memories (recent experiences) results in ______ amnesia, whereas difficult in retrieving memories already established is ______ amnesia.

Pathological Anterograde Retrograde

Fornix pathways: -a pathway to the hypothalamus (the part that goes in front of the anterior commissure- _____commissural) -a major projection to the mammillary bodies (_____commissural).

Pre Post

________ is a phenomenon that demonstrates the continual transfer of information from ______ memory into _____ term memory whether or not there is an _____ to remember it. -usually demonstrated by exposing subjects to items in their environment without an ______ to remember them and then showing that this exposure affects recall.

Priming Working- longterm Intent Effort

Huntington's disease and Parkinson's disease are examples of pathologies which affect _________ memory.

Procedural

_______ memory involves learned behaviors, usually in the form of motor tasks or sequences.

Procedural

In such patients, _____ memory is often intact, and ______ testing may indicate normal or even above normal. In general, _____ injury is required to produce appreciable deficits in this system (but not always).

Procedural Intelligence Bilateral

The difference may be the inclusion of being able to use the items as well as ______ them.

Remembering

The emotional affect and ______ nature of behaviors that are involved in memories and remembered actions also involve some ______ structures; depends on ______

Rewarding Subcortical Dopamine

It is now clear that forgetting is an important process in the _____ of information that is incorporated.

Selectivity

The amygdaloid complex connects directly and indirectly connects to the _____ area (nuclei), the hypothalamus, the nucleus accumbens and rostral areas of the caudate nucleus and putamen. It has large input from areas associated with ____ and ______

Septal Taste and olfaction

Emotional loop Among the most important of these are the amygdala, ______, the nucleus ______ and the ventral tegmental area of the brainstem.

Septal nuclei Nucleis accumbens

Patients with isolated lesions of this system have immediate and some _____ term memory, but cannot consolidate information into _____ term memory.

Short Long

One important mechanism to add significance to memory is emotional affect. Memories that are "_______" usually have intense ______responses and affect associated with them.

Significant Autonomic

The fact that patients with memory consolidation deficits can be shown to retain the ability to acquire procedures or non-declarative memory indicates that these memories have a different _____

Substrate

The amygdala appears to add a "_______" autonomic component to memory as part of formation and recall. Its connections with the hypothalamus are believed to be the mechanism for memory associated _____ responses.

Sympathetic Autonomic

These circuits involve the basal nuclei, prefrontal cortex, amygdala, sensory association cortex and cerebellum, but not those of the _____ or _____

Temporal lobe or midline thalamic nuclei

This area of cortex has broad ______ way communication with areas including prefrontal areas, premotor areas, visual, auditory and somatosensory association cortex. -This communication forms the basis for certain types of _____

Two way Memory

______ memory is information held for a short period of time in order to accomplish a task.

Working

______ memory (aka-______ term memory)- ability to hold information in mind for access for seconds to minutes after the present. -One Clinical test is to remember a span of digits presented; ____ is normal. -Another is a list of several _____ to be recalled later in an interview.

Working (short) 7-9 Several