NSCI 1001 - Aging

Aging lectures (parts 1 & 2)

Aging

Time-related deterioration of the psychological functions necessary for survival and fertility

Senescent Phenotype

Characteristic aging features specific to each species.

Oxidative Damage Theory

Aging as a by-product of normal metabolism.

Reactive Oxygen Species (ROS)

Oxygen atoms reduced insufficiently during ATP production.

Oxidative Stress

Damage occurs when ROS exceeds neutralization capacity.

Free Radical Theory

Proposed by Harman, ROS mediates the aging process.

Wear-and-Tear Theory

Accumulation of small traumas contributes to aging.

Genetic Instability

Increased point mutations and decreased enzyme efficiency.

DNA Repair Importance

Efficient DNA repair may prevent cellular senescence.

Hutchinson-Gilford Progeria Syndrome

Genetic disorder causing rapid aging in children.

Grey Matter Changes

Volume decreases with age, affecting nerve cells.

White Matter Changes

Increases from ages 19-40, then declines.

Brain Shrinkage

Overall brain volume decreases starting in the 30s.

Structural Magnetic Resonance Imaging (sMRI)

Technique for detailed brain anatomy imaging.

Functional Magnetic Resonance Imaging (fMRI)

Studies brain activation patterns during aging.

Medial Prefrontal Cortex (mPFC)

Region showing reduced activation correlation in older adults.

Posterior Cingulate (pC)

Part of the brain with altered activation in aging.

Lateral Parietal Cortex (LP)

Region with less localized neural activity in older adults.

Neural Activity Localization

Older adults show less discrete brain region activation.

Positron Emission Tomography (PET)

Imaging technique showing brain activation during memory tests.

Right-Lateralized Activation

Young adults exhibit this during memory task performance.

Right-lateralized PFC activity

Brain activity pattern linked to poor cognitive performance.

Bilateral activation

Brain activity pattern associated with good cognitive performance.

Functional magnetic resonance imaging (fMRI)

Non-invasive technique measuring brain activity via blood flow.

Positron Emission Tomography (PET)

Imaging test using radioactive tracer to visualize brain function.

Episodic memory

Memory type storing information with contextual 'mental tags'.

Age-associated memory impairment

Normal age-related forgetfulness affecting cognitive function.

Mild cognitive impairment

More serious memory problems beyond normal aging signs.

Dementia

Loss of cognitive function interfering with daily life.

Alzheimer's disease

Common type of dementia characterized by memory loss.

Lewy body dementia

Dementia type with visual hallucinations and movement issues.

Frontotemporal dementia

Dementia affecting personality and behavior changes.

Vascular dementia

Dementia caused by reduced blood flow to the brain.

Synaptic plasticity

Ability of synapses to strengthen or weaken over time.

Neurodegeneration

Gradual decline of neuron function leading to cell death.

Pathological protein aggregation

Protein clumping indicating neurodegenerative disease presence.

Neuronal network dysfunction

Impaired communication between neurons affecting brain function.

Aberrant proteostasis

Disruption in protein homeostasis contributing to neurodegeneration.

Cytoskeletal abnormalities

Structural changes in neurons leading to dysfunction.

Altered energy metabolism

Impaired energy production affecting neuron survival.

DNA and RNA defects

Genetic abnormalities contributing to neurodegenerative diseases.

Inflammation

Immune response linked to neurodegeneration processes.

Neuronal cell death

Loss of neurons impacting cognitive and motor functions.

Neuroinflammation

Inflammation within the nervous system affecting neurons.

Gliosis

Proliferation of glial cells in response to CNS injury.

Neurodegenerative Diseases (NDDs)

Disorders characterized by neuronal loss and dysfunction.

Amyloid Precursor Protein (APP)

Protein associated with Alzheimer's disease pathology.

Tau

Protein linked to Alzheimer's and tauopathies.

Alpha-synuclein (SNCA)

Protein involved in Parkinson's and synucleinopathies.

Huntingtin (Htt)

Protein associated with Huntington's disease (HD).

Neurofibrillary Tangles

Cytoskeletal abnormalities found in Alzheimer's disease.

Amyloid Plaques

Extracellular aggregates of amyloid-beta in Alzheimer's.

Substantia Nigra Pars Compacta (SNpc)

Brain region with lost dopaminergic neurons in PD.

Lewy Bodies

Aggregated α-synuclein inclusions in Parkinson's disease.

Episodic Memory

Memory type affected early in Alzheimer's disease.

Cognitive Difficulties

Impairments in thinking and attention in Alzheimer's.

Microgliosis

Proliferation of microglia in response to CNS damage.

Astrogliosis

Proliferation of astrocytes due to CNS injury.

Early-Onset Alzheimer's

AD occurring before age 65, often genetic.

Late-Onset Alzheimer's

AD starting at age 65 or later, mostly age-related.

APOE Gene Polymorphisms

Genetic variations influencing Alzheimer's risk.

Risk Factors for AD

Genetic and age-related factors contributing to Alzheimer's.

Non-Motor Symptoms of PD

Symptoms like hyposmia and sleep disturbances in PD.

Neuronal and Synaptic Loss

Reduction in brain weight due to neuronal damage.

Inflammatory Response

Body's immune reaction that can harm or protect neurons.

Dopaminergic Neurons

Neurons that produce dopamine, crucial for movement.

SNCA Aggregates

Protein aggregates linked to Parkinson's disease pathology.

Sporadic PD

Parkinson's disease linked to age and lifestyle factors.

Global PD Prevalence

Expected to double in the next decade.

Neuronal Selectivity

Specific neuron groups affected in Parkinson's disease.

Substantia Nigra (SN)

Brain region crucial for motor control and reward.

Basal Ganglia

Group of structures essential for movement coordination.

Dopamine Reduction

Loss of dopamine neurons causes motor symptoms.

Striatal Neuron Vulnerability

Striatal neurons are particularly susceptible in PD.

Mitochondrial Dysfunction

High energy demand makes neurons vulnerable to stress.

Oxidative Stress

Increased ROS levels damage dopaminergic neurons.

Calcium Imbalance

Elevated calcium levels contribute to oxidative stress.

Neurodegenerative Treatments

Focus on symptom management and quality of life.

Cholinesterase Inhibitors

Medications that prevent acetylcholine breakdown.

Acetylcholine Production

Decreases as Alzheimer's disease progresses.

Lecanemab

FDA-approved drug targeting beta-amyloid in Alzheimer's.

Donanemab

Immunotherapy for reducing amyloid plaques in Alzheimer's.

Levodopa

Gold standard medication for Parkinson's motor symptoms.

Dopamine Agonists

Medications like pramipexole used in early PD stages.

Deep Brain Stimulation (DBS)

Surgical treatment using electrodes to reduce motor symptoms.

Quality of Life Improvement

DBS can enhance life quality for poorly managed patients.

Aging Affected Brain Areas

Entorhinal cortex, substantia nigra, and striatum.

Physiological functions

Functions necessary for survival and fertility.

Average life span increase

15 years in high-income, 30 years in low-income countries.

Oxidative damage

Aging as a by-product of normal metabolism.

Reactive Oxygen Species (ROS)

Byproducts of metabolism causing cellular damage.

Mitochondria

Cell organelles that produce ATP via oxidative phosphorylation.

Oxidative stress

Damage from excess ROS production.

Free radical theory

ROS as primary mediators of aging process.

Wear-and-tear theory

Aging due to accumulated small bodily traumas.

DNA repair

Mechanism preventing senescence and prolonging lifespan.

Hutchinson-Gilford progeria syndrome

Rapid aging syndrome caused by a dominant gene.

Progeria symptoms

Thin skin, hair loss, bone mass loss.

Brain aging

Structural and functional changes in the aging brain.

Grey matter

Volume decreases with age, affecting nerve cells.