AGING AND MEMORY The aging of America Conventional wisdom on aging and memory Neurobiological changes [demo][demo] –Neural mass decreases, 5-10% / decade Shrinkage; atrophy of “white matter” Frontal lobes particularly vulnerable Some atrophy, little cell loss, in hippocampus –Decreases in neurotransmitters Acetylcholine from basal forebrain Dopamine receptors in frontal lobes –Decreased blood flow, metabolism –Less “functional activation” Left anterior frontal during encoding Right anterior frontal during retrieval

HOW MEMORY CHANGES The myth of inevitable, global decline Deficits may be due to other factors: –General health problems –Medication –Depression –Self-concept, sense of “efficacy” –Educational level –Motivation and task engagement –Specific disease (e.g., Alzheimer’s)

Age-related declines seen... More inThan in Kinds of memory: declarativeprocedural explicitimplicit episodicsemantic recentremote Types of tasks: complexsimple tasks unfamiliarfamiliar tasks distractorno distractor dividedfull attention recallrecognition

Processes that are especially vulnerable: –Speeded information processing (the “general slowing hypothesis” of Salthouse) –Effortful, strategic encoding, more so retrieval (the “reduced resources hypothesis” of Craik) –Source monitoring and memory –Executive function, elaborative encoding and retrieval Simon (1979): Cued recall The farmer drove the truck FreeCued Young Old.25.25

(Cherry, et al. 1993): contextual cues and “causal elaborations” The grimacing man held the cheese.... as he reached for a salt cracker. (nonexplanatory context).. as the mousetrap caught his finger. (explanatory context) Type of context nonexplanatory explanatory Base FullBase Full Young Old

–Executive control in working memory (Baddeley) Salthouse & Babcock (1991) : “computation span” –Attentional allocation, inhibition of potential distractors from task or memory (Hasher & Zacks) Broader context-priming effects Greater stroop interference More PI intrusions

AGING AND MEMORY Taking the edge off aging –Stay healthy and engaged Regular aerobic exercise Nonroutine, challenging daily activities –Provide meaningful organization and structure to tasks –Allow adequate time for encoding and retrieval –Minimize distractions, keep tasks simple –Provide extensive practice on new tasks, continued practice on old skills Reminiscence in the elderly –Seeing coherence in one’s life story –Providing continuity over the generations

Mental Exercise and Mental Aging The “use it or lose it’ hypothesis –Evidence of “protective function” of mental activity Rutgers NewsletterRutgers Newsletter –Salthouse (06): the need for longitudinal comparisons

Suggests that mental activity does not Affect rate of decline with age

Alzheimer’s and Memory Demographics –C. 4 million afflicted, accelerates with aging (50% of 85 yr+) –3 rd leading cause of death –Costs approaching $100 billon annually Etiology –Ultimate causes unknown –Immediate cause is degeneration of neural structure Loss of mass, neurons Impaired acetylcholine levels Plaques of neural debris Neurofibrillary tangles within neurons

Early symptoms of dementia –Memory loss: misplacing things, forgetting to do things, disorientation, repetition in converstation, retrieval of familiar words and names –Procedural memory: deficits in performance of “simple” routine tasks; dressing, cooking, etc –Poor judgment: e.g., wrong clothes, inappropriate social behavior Progressive Dementia –Increasingly severe impairment in cognitive functioning; semantic memory, language, autobiographical memory –Loss of motor control –Loss of self –The challenge to families

fMRI and aging Memory Retrieval (Miller, 03) Top row: young adult (20 yr) Bottom row: old adult (70 yr)

Source Memory Problems and Aging Session 1: view nonfamous faces detect repetitions Session 2 (next week): view S1 faces, other famous and nonfamous faces judge fame

Episodic Memory Deficits in Alzheimer’s Disease La Rue, 1992: WMS loss (%) Paired associate recall 34 Paired associate recognition 5 Memory for visual detail 65 Story memory 80