CiCC - Memory - Dementia

CiCC – Memory – Dementia

Dementia = collection of symptoms associated with impaired cognitive abilities and ability to carry out every day activities. Symptoms include:

  • Memory loss

  • Difficulty sustaining attention

  • Language

  • Disorientation in space and time

  • Hallucinations/delusions

  • Mood changes

Dementia is NOT a diagnosis but can be caused by a number of different biological diseases/factors affecting the brain

850000 people in the UK with dementia. Alzheimer’s is the most common cause 60-70%.

Alzheimer’s

Neurodegenerative disease which involves deterioration in cognitive abilities. Appears around age 60. There are individual differences in symptom progression.

Atrophy in Alzheimer’s

Using sMRIs we have found Neuronal loss (reduction in grey and white matter) In a topographical progression throughout the brain.

Hippocampal Atrophy and Memory

Brain slices have shown gradual loss of hippocampal volume in people with mild cognitive impairment (over 36 months)

Neurotransmitter Impairments

  • Synaptic dysfunction

  • Loss of Cell bodies in nucleus basalis

  • Cell bodies produce acetylcholine

  • Medications to reduce dementia symptoms boost the brain’s supply of acetylcholine

Abnormalities in Proteins required for Neuron maintenance

Measuring in vivo

In order to measure localisation

  • Blood tests

  • PET scans

  • Cerebrospinal fluid

Localisation of Amyloid

Beta amyloid deposition first occurs in the posterior cingulate cortex, pre cuneus and medial prefrontal cortex.

Localisation of Tau

Tau deposition follows Braak staging (localised to the MTL) in early stages of disease

Biomarker Profile

Beta amyloid and tau deposition can occur without clinical dementia. 25% of healthy adults have vastly different levels of each (despite being healthy). Abnormal deposits drive neurodegeneration and progression to Alzheimer’s disease.

Types of memory affected by Alzheimer’s Disease

  • Episodic (long and short term)

  • Working Memory

  • Spatial Memory

  • Semantic Memory

How do we assess memory impairment?

  • Novel Methods (VR tests of spatial memory)

  • In Clinic Assessment

Changes in real life behaviour

Rusted and Sheppard monitored Tea Making abilities of people living with dementia. ***

Risk factors for Alzheimer’s

How do we detect who will develop Alzheimer’s

There are huge individual differences in the impact and age of neurodegenerative disease.

Risk Factors

  • Age (biggest one)

  • Genes (deterministic genes (on chromosomes 21 and 14) and risk genes (on chromosome 19))

APOE e4

Those with a copy of the e4 allele (e3-34 / e4-e4 🡨worst) are at a greater risk of Alzheimer’s

Modifiable risk factors

  • Less education (childhood)

  • Obesity/ Hearing Loss (Mid-life)

  • Smoking, Depression, Physical Inactivity, Diabetes (Late Life)