12b memory pt 2

What is dementia?

Dementia is an acquired, persistent decline involving memory plus at least two other cognitive domains, such as language, judgment, or spatial ability, with meaningful interference in daily functioning. It is broader than ordinary forgetfulness or one isolated memory problem. Slide 4.

What major conditions can cause dementia?

Causes include infection, such as AIDS-related disease or neurosyphilis; metabolic problems, such as alcoholism or vitamin B deficiency; repeated trauma and CTE; vascular disease associated with diabetes or hypertension; and neurodegeneration, including Alzheimer’s disease. Slide 4.

How are dementia and Alzheimer’s disease different?

Dementia is a syndrome describing persistent decline across memory and other cognitive functions. Alzheimer’s disease is a specific neurodegenerative disease and a major cause of dementia; dementia can also arise from several non-Alzheimer causes. Slide 4.

What did Dr. Alois Alzheimer contribute in 1906?

He described a patient with progressive cognitive symptoms and examined unusual protein aggregates in her brain after death. Linking the clinical decline with brain pathology helped define the disease later named Alzheimer’s disease. Slide 7.

How do anterograde and retrograde memory loss typically progress in Alzheimer’s disease?

Difficulty forming new conscious memories usually appears early, so recent meals or conversations are forgotten. As disease progresses, retrograde loss expands backward through the past, with recent memories generally affected before remote childhood memories. Slide 7.

A person remembers childhood but repeatedly forgets what happened this morning. What does this suggest?

It suggests prominent anterograde impairment with relative preservation of remote memory, a common early Alzheimer’s pattern. The person cannot reliably consolidate recent events even though older memories remain accessible. Slide 7.

What language changes can occur in Alzheimer’s disease?

Anomia causes difficulty naming familiar objects or people. Empty speech uses many words without specific information, while talking in circles is repetitive speech that never reaches a clear answer. These problems worsen as the disease progresses. Slide 7.

What other cognitive and behavioural changes accompany Alzheimer’s memory loss?

Spatial disturbance can cause disorientation or getting lost; impaired awareness may lead to denial and unsafe decisions; psychosis may emerge later. Early sensory and motor abilities can remain relatively intact despite serious cognitive decline. Slide 7.

What is sundowner syndrome?

Sundowning is increased confusion and behavioural disturbance near the end of the day, including agitation, restlessness, wandering, screaming, and disorientation. Fatigue and reduced ability to compensate may make symptoms more apparent in the evening. Slide 8.

What characterizes very early and mild Alzheimer’s disease?

Very early disease may appear as amnestic mild cognitive impairment, with greater-than-expected memory lapses but relative independence. Mild disease brings intensified memory trouble, confusion, impaired basic skills and judgment, and subtle mood or personality changes. Slide 9.

What characterizes moderate and severe Alzheimer’s disease?

Moderate disease substantially impairs language, reasoning, learning, and conscious thought; confusion and psychosis can increase. Severe disease profoundly impairs communication and daily functioning, requiring extensive care. Slide 10.

How does Alzheimer’s disease progress across stages?

The typical sequence is amnestic mild cognitive impairment, mild Alzheimer’s disease, moderate disease, and severe disease. Difficulties broaden from subtle memory lapses to impaired judgment and skills, then major language and reasoning problems, and finally profound communication and care needs. Slides 9-10.

What is the Mini-Mental State Examination?

The MMSE is a brief 30-point examination sampling orientation, registration, attention or calculation, delayed recall, language, command following, and visuospatial construction. Repeated scores can help document cognitive change over time. Slide 11.

How does the MMSE test orientation and memory?

Questions about the date and current location test orientation to time and place. Repeating three named objects tests registration, while recalling them after a delay tests retention and retrieval of recent information. Slide 11.

How does the MMSE test attention, language, and visuospatial ability?

Serial sevens or spelling WORLD backward test attention and working memory. Naming, repetition, reading, writing, and following commands sample language. Copying intersecting pentagons tests visuospatial construction. Slide 11.

A patient repeats three words correctly but cannot recall them later. What does this MMSE pattern mean?

Immediate registration was adequate, but delayed retention or retrieval was impaired. This points more specifically to a memory deficit than to failure to hear, understand, or initially repeat the words. Slide 11.

How should an MMSE score be interpreted in Alzheimer’s disease?

Scores generally decline as disease advances, so repeated testing can help track progression. One MMSE score cannot independently diagnose Alzheimer’s disease because diagnosis requires a broader clinical assessment. Slides 11-12.

What does the Alzheimer’s progression graph show?

Symptoms can begin before formal diagnosis. As MMSE scores fall, functional independence is lost, behavioural problems become more prominent, and nursing-home care becomes more likely; scores approach very low levels in severe disease. Exact timing varies between people. Slide 12.

What large-scale brain changes occur in Alzheimer’s disease?

The brain loses volume through cortical atrophy: the cortex and gyri thin, sulci widen, ventricles may appear enlarged, and medial temporal structures show marked degeneration. These changes produce the characteristic shrunken appearance. Slide 13.

Why is hippocampal atrophy important in Alzheimer’s disease?

The hippocampal region is crucial for forming new declarative memories. Severe bilateral degeneration helps explain why inability to create new conscious memories is an early and prominent symptom. Slides 7 and 13.

What are the two major microscopic markers of Alzheimer’s disease?

The hallmarks are neurofibrillary tangles formed mainly from abnormal tau inside neurons and beta-amyloid plaques deposited outside neurons. Both disrupt neural function and are associated with cell loss. Slide 14.

What are neurofibrillary tangles?

Tangles are abnormal accumulations of tau protein inside neurons. Because altered tau cannot properly support cellular structure and transport, the neuron becomes dysfunctional and may die. Slide 14.

What are beta-amyloid plaques?

Plaques are extracellular clumps produced when amyloid precursor protein is processed in a way that permits beta-amyloid fragments to aggregate. The deposits disrupt surrounding neural tissue and communication. Slide 14.

How do tangles and plaques differ?

Tangles consist mainly of abnormal tau and form inside neurons, disrupting internal structure and transport. Plaques consist of aggregated beta-amyloid and form outside neurons, disturbing communication and surrounding tissue. Slide 14.

Why is finding some beta-amyloid not definitive proof of Alzheimer’s disease?

Some amyloid deposition can occur in people without clinically diagnosed Alzheimer’s disease. Diagnosis depends on the overall clinical and pathological pattern rather than the mere presence of any amyloid. Slide 14.

What happens to the basal forebrain cholinergic system in Alzheimer’s disease?

Basal forebrain cholinergic neurons degenerate, especially by moderate-to-severe disease. This reduces acetylcholine signaling to cortical and memory-related regions and contributes to cognitive impairment. Slide 15.

What can current symptomatic treatment and protective lifestyle factors do?

Some drugs increase remaining acetylcholine signaling and may temporarily support cognition, but they do not cure the underlying degeneration. Healthy diet and exercise may help delay risk, while education may provide cognitive reserve and compensatory strategies; none guarantees prevention. Slide 15.

How would you distinguish ordinary forgetfulness, amnestic MCI, and dementia?

Ordinary forgetfulness does not produce persistent broad functional decline. Amnestic MCI involves greater-than-expected memory difficulty with relative preservation of independence. Dementia requires acquired, persistent memory impairment plus decline in at least two other domains that disrupts everyday functioning. Slides 4 and 9.

Explain the typical progression of Alzheimer’s disease from very early to severe stages.

Very early disease may appear as amnestic MCI. Mild disease intensifies memory problems and introduces confusion, impaired skills and judgment, and subtle mood changes. Moderate disease substantially affects language, reasoning, learning, and reality testing. Severe disease impairs communication and requires extensive care. Slides 9-10.

Explain how the MMSE samples different cognitive domains.

Orientation questions test time and place; immediate repetition tests registration; serial sevens or backward spelling test attention and working memory; delayed recall tests memory; naming, repetition, reading, writing, and commands test language; copying pentagons tests visuospatial construction. Slide 11.

Explain Alzheimer’s pathology at the macroscopic and microscopic levels.

Macroscopically, brain volume declines: cortex and gyri thin, sulci widen, and hippocampal structures atrophy. Microscopically, intracellular tau tangles and extracellular beta-amyloid plaques disrupt neurons. Basal forebrain degeneration also reduces acetylcholine signaling. Slides 13-15.

A patient forgets recent conversations, calls objects “things,” becomes lost in a familiar building, but still walks and sees normally. How does this fit Alzheimer’s disease?

Recent-memory failure suggests anterograde impairment; vague naming suggests anomia or empty language; getting lost suggests spatial disturbance; preserved walking and vision fit the relative lack of early motor and sensory deficits. Slide 7.

Why can Alzheimer’s disease ultimately be fatal?

Progressive neurological decline can cause immobility, swallowing problems, infection, injury, and inability to manage basic needs. Another complication may be recorded as the immediate cause of death, but advanced Alzheimer’s substantially contributes to the fatal outcome. Slide 3.