Memory: Amnesia and Memory Disorders, Universidad Europea Presentation

Memory and Learning Processes

ue 2024/2025 David Prada CrespoAMNESIA AND MEMORY DISORDERS Universidad Europea

Memory Disorders and Brain Areas

Memory disorders are closely related to impaired brain areas.

A Prefrontal Cortex Memory involving the sequence of events, but not the events themselves

Amygdala Encodes emotional aspects of memories

Medial Temporal Lobe (not visible) Encodes and transfers new explicit memories to long- term memory

Hippocampus Encodes and transfers new explicit memories to long-term memory

Cerebellum Memories involving movement

Distortions vs. Memory Disorders

We can distinguish between distortions and memory disorders:

• Distortions: Everyone forgets names, dates and events. This forgetfulness is normal and no one should be alarmed.
• Disorders: These create serious impairment Universidad Europea

Seven Sins of Memory

Seven sins of memory https://www.youtube.com/watch?v=T7QUPKmeHmA Los siete pecados de la emoria redes memoria y evolución Redes 09: Los siete pecados de la memoria https://www.youtube.com/watch?v=reZ4YrgjuRo Universidad Europea

Memory Activity

Los siete pecados de la memoria Activity 1. Explain the seven sins of memory mentioned by Schachter. 2. Describe one example of every memory failure in your own life. Universidad Europea

Memory Distortions by Daniel Schacter

we Daniel Schacter (The seven sins of memory, 2001) considers that these failures are not biological deficiencies, but an instrument of survival. In fact, forgetting is as important as remembering.

• Transience: the decreasing accessibility of memory over time. While a degree of this is normal with aging, decay of or damage to the hippocampus and temporal lobe can cause extreme forms of it.
• Absent-mindedness: lapses of attention and forgetting to do things. This sin operates both when a memory is formed (the encoding stage) and when a memory is accessed (the retrieval stage).
• Blocking: temporary inaccessibility of stored information, such as tip-of-the-tongue syndrome. Universidad Europea

Omission Errors in Memory

we Daniel Schacter (The seven sins of memory, 2001) considers that these failures are not biological deficiencies, but an instrument of survival. In fact, forgetting is as important as remembering.

. Transience: the decreasir time. While a degree of or damage to the hippocamp cause extreme forms of it.

Omission errors

• Absent-mindedness: lapses of attention and forgetting to do things. This sin operates both when a memory is formed (the encoding stage) and when a memory is accessed (the retrieval stage).
• Blocking: temporary inaccessibility of stored information, such as tip-of-the-tongue syndrome. Universidad Europea

Memory Distortions: Suggestibility, Bias, Persistence, Misattribution

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• Suggestibility: incorporation of misinformation into memory due to leading questions, deception and other causes (False memories of Elizabeth Loftus and Stephen Ceci)
• Bias: retrospective distortions produced by current knowledge and beliefs
• Persistence: unwanted recollections that people can't forget, such as the unrelenting, intrusive memories of post-traumatic stress disorder.
• Misattribution: attribution of memories to incorrect sources or believing that you have seen or heard something you haven't. Universidad Europea

Commission Errors in Memory

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• Suggestibility: incorporation of misinformation into memory due to leading questions, deception and other causes (False memories of Elizabeth Loftus and Stephen Ceci)
• Bias: retrospective distortions produced by current knowledge and beliefs
• Persistence: unwanted forget, such as the unrelent. post-traumatic stress disorder.

Commission errors

• Misattribution: attribution of memories to incorrect sources or believing that you have seen or heard something you haven't. Universidad Europea

Amnesia: Total or Partial Memory Loss

Amnesia is the total or partial loss of memory. In its pure form, the amnesic syndrome involves grossly impaired episodic memory, together with preserved working memory, semantic memory, implicit memory and intelligence. Usually, its cause is organic (infection, traumatic brain injury, anoxia, Korsakoff syndrome, neurodegenerative disorders, etc.). There are two types of organic amnesia:

Anterograde amnesia Inability to acquire new information and remember the events produced after a brain injury

Retrograde amnesia Inability to remember the past, facts produced before the brain injury. Universidad Europea

Anterograde Amnesia Characteristics

Anterograde Amnesia

• Inability to acquire new episodic and/or semantic memories
• e.g., Resection (H.M.), Alzheimer disease, traumatic brain injury, stroke ...

Contracción extrema de la corteza cerebral Dilatación grave de los ventrículos Contracción extrema del hipocampo

• Events occurring before the injury are generally remembered without problems but those occurring after the injury occur are not retained in the patient's memory.
• Other memory systems can be functional (Working memory, implicit long-term memory ... )

Future New memories Inability to form new memories. Anterograde amnesia

Time point of brain injury

Retrograde amnesia

Old memories len Preserved old memories

Past Inability to access old memories. Retrograde amnesia may be incomplete, with older memories being accessible, whereas more- recent memories are not. Universidad Europea

Anterograde Amnesia and Memento

Anterograde Amnesia

ew episodic and/or semantic Alzheimer disease, traumatic

Contracción extrema de la corteza cerebral Dilatación grave de los ventrículos Contracción extrema del hipocampo

ore the injury are generally t problems but those jury occur are not retained

• Other memory systems can be functional (Working memory, implicit long-term memory ... )

Future Inability to form new memories. New memories Anterograde amnesia

Time point of brain injury

Retrograde amnesia

Old memories len Preserved old memories

Past Inability to access old memories. Retrograde amnesia may be incomplete, with older memories being accessible, whereas more- recent memories are not. Universidad Europea

GUY PEARCE CARRIE-ANNE MOSS JOE PANTOUAND MEMENTO I in the patient's memory.

Retrograde Amnesia: Accessing Old Memories

Retrograde Amnesia

• Inability to access old memories
• May be incomplete-older memories accessible but more recent memories are not
• e.g., Alzheimer's disease: occurs when brain damage is extended to other brain areas (e.g., lateral temporal cortex). e.g., Alzheimer's disease: That cortical areas are not impaired in the first stages of the illness (that's why the patient can remember old episodes).

Corteza de asociación auditiva (área de Wernicke) Corteza auditiva primaria Giro temporal (áreas 41 y 42) superior

• e.g., Traumatic brain injury: severity of injury determines how far back in time the amnesia extends.

Future Inability to form new memories. New memories Anterograde amnesia

Time point of brain injury

Retrograde amnesia

Old memories Preserved old memories

Inability to access old memories. Retrograde amnesia may be incomplete, with older memories being accessible, whereas more- recent memories are not. Past Universidad Europea

Retrograde Amnesia and The Bourne Identity

Retrograde Amnesia

• Inability to access old memories
• May be incomplete-older memories accessible but more recent memories are not
• e.g., Alzheimer's disease: occurs when brain damage is extended to other brain areas (e.g., lateral temporal cortex). e.g., Alzheimer's disease: That cortical areas are not impaired in the first stages of the illness (that's why the patient can remember old episodes).

Corteza de asociación auditiva (área de Wernicke) Corteza auditiva primaria Giro temporal (áreas 41 y 42) superior

• e.g., Traumatic brain injury: severity of injury determines how far back in time the amnesia extends.

BOURNE THE ULTIMATE S-MOVIE COLLECTION SS Old memorie Preserved old memories

Past Retrograde amnesia may be incomplete, with older memories being accessible, whereas more- recent memories are not. Universidad Europea

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Impairment of New Explicit Information Storage

Medial Temporal Cortex and Hippocampus

Medial temporal cortex and hippocampus:

Hippocampus areas:

• Dentate Gyrus - Cells are stellate Granule Cells - "Sensory" cells
• Amnon's Horn - Contains pyramidal cells divided into 4 groups, CA1, CA2, CA3, CA4
• Fimbria-fornix - Connects the hippocampus to other nuclei and áreas: thalamus, hypothalamus, associative cortex (e.g. prefrontal cortex) ...

(A) Cingulate gyrus Fimbria-fornix Mammillary Hippocampus bodies Perforant pathway

(B) CA3 CA2 Ammon's CA4 -horn CA1 Dentate gyrus

(C) Mammilary bodies Anterior thalamus Nucleus accumbens Hippocampal formation Subiculum CA1 CA3 DG Entorhinal cortex Other direct projections Perirhinal cortex Parahippocampal cortex Neocortex 2 8

Alzheimer's Disease and Hippocampal Neurodegeneration

Impairment of New Explicit Information Storage

Medial temporal cortex and hippocampus:

Hippocampus areas:

• Dentate Gyrus - Cells are stellate Granule Cells - "Sensory" cells
• Amnon's Horn - Contains pyramidal cells divided into 4 groups, CA1, CA2, CA3, CA4
• Fimbria-fornix - Connects the hippocampus to other nuclei and áreas: thalamus, hypothalamus, associative cortex (e.g. prefrontal cortex) ...

(A) (C) Cingulate gyrus Fimbria-fornix Mammilary bodies Anterior thalamus Nucleus accumbens Hippocampal formation Subiculum CA1

Mammillary Hippocampus bodies Perforant pathway

Alzheimer's disease: Neurodegeneration starts in the entorhinal cortex and extends to other areas of the hippocampus and the medial temporal lobe > Storage of new explicit information is impaired! No consolidation of new explicit information!

Ammon's -horn -CA1 × Other direct projections Perirhinal cortex Parahippocampal cortex Neocortex 2 9 CA3 DG e gyrus

Korsakov's Syndrome and Thiamine Deficiency

Impairment of New Explicit Information Storage

Medial temporal cortex and hippocampus:

Hippocampus areas:

• Dentate Gyrus - Cells are stellate Granul Cells - "Sensory" cells
• Amnon's Horn - Contains pyramidal cell divided into 4 groups, CA1, CA2, CA3, CA4
• Fimbria-fornix - Connects the hippocampus to other nuclei and áreas: thalamus, hypothalamus, associative cortex (e.g. prefrontal cortex) ...

(A) (C) milary ho Cingulate gyrus Fimbria-fornix Ant MUS

Korsakov's syndrome: Caused by thiamine (vitamin B1) deficiency resulting from prolonged alcohol intake. Disruption of diencephalic structures (thalamus, mammillary bodies) and frontal lobe. Symptoms: anterograde and retrograde amnesia, confabulations, lack of awareness of the deficit, etc.

Hippocampal formation Subiculum CA1 DUS CA3 DG mon's -horn -CA1 Entorhinal cortex Other direct projections rus Perirhinal cortex Parahippocampal cortex Neocortex 3 1