Memory and Aging: Figure Analyses and Exam Questions (Questions 1-5)

Study Setup and Participants

  • Topic: Memory processes in Alzheimer's disease (AD) patients vs adults with normal memory.
  • Participants:
    • Alzheimer's disease (AD) patients, age range 60-80 years.
    • Control group: adults without memory impairments divided into three age groups: 20-39, 40-59, and 60-80. The two younger groups (20-39 and 40-59) showed no significant difference and are combined for certain analyses.
  • Stimulus: a list of 21 unrelated words presented at a rate of one word every 3 seconds.
  • After the final word, participants completed immediate recall of as many words as possible, then a recognition task.
  • List order was the same for all groups.
  • Figures:
    • Figure 1: recall and recognition performance (for each group, including AD).
    • Figure 2: percentage of recall from beginning (primacy), middle, and end (recency) of the list. The control groups (20-39 and 40-59) are combined in Figure 2.
  • Additional finding: control participants retrieved words semantically related to items on the list that had not actually appeared (false memory risk).
  • Important methodological note: the AD data are restricted to the 60-80 age range, limiting conclusions about age-related progression of AD from Figure 1.
  • The data align with classic memory theory: recall generally declines with age; recognition is relatively more stable; false memories can arise from semantic associations; serial position effects reveal underlying memory system distinctions.

Figure 1: Recall and Recognition Data (interpretation cues)

  • Key takeaway: recall declines with age in the AD and control groups, whereas recognition remains fairly stable across age groups in controls.
  • AD data are limited to the 60-80 age range, so age-related progression of AD cannot be inferred from Figure 1 alone.
  • For controls, recall is lower than recognition across ages (recognition generally superior to recall).
  • The list was the same order across all groups, enabling direct group comparisons on recall and recognition given identical stimuli.

Figure 2: Serial Position Effects in Recall (control vs AD)

  • Figure 2 shows the percentage of words recalled as a function of their position in the list (beginning/primary, middle, end/recency).
  • Control groups (20-39 and 40-59) combined: robust primacy effect (better recall for early items) and strong recency effect (better recall for last items) observed in free recall.
  • Alzheimer’s patients (60-80) show a markedly different pattern, with a clear impairment in recall for items from the early part of the list (primary effect) and a relatively preserved recency portion only to the extent allowed by any remaining memory function. The data specifically indicate a poor recall for the early items but not a complete absence of late-item recall.
  • Important distinction: the AD data cannot be generalized to explain overall aging versus disease progression due to the age range limitation.

Question 1: Which statement is not supported by the data in Figure 1?

  • Options:
    • A. As people grow older, their ability to recall declines.
    • B. Recognition is relatively stable in adults without memory impairments.
    • C. The memory problems in Alzheimer's disease are an acceleration of the aging process.
    • D. Participants without memory impairments perform better in the recognition task compared to the recall task.
  • Correct answer: C
  • Rationale:
    • A: Supported by Figure 1, which shows recall performance decreasing with age.
    • B: Supported by Figure 1, which shows recognition remaining fairly stable across age groups in controls.
    • C: Not supported because Figure 1 includes AD data limited to 60-80; it does not establish that AD is simply an acceleration of aging.
    • D: Supported by Figure 1, since recognition is generally better than recall for controls.
  • Key takeaway: Figure 1 demonstrates age-related declines in recall and relative stability of recognition in controls, but cannot attribute AD progression purely to aging due to the AD age range limitation.

Question 2: The finding in the last paragraph regarding the retrieval of related words supports which concept?

  • Options:
    • a) spread in activation
    • b) depth of processing
    • c) the serial position effect
    • d) the existence of Visuospatial Sketchpad
  • Correct answer: a
  • Rationale:
    • a) Spread of activation: Semantically related words become activated from the representations of presented words, leading to related yet non-presented words being recalled—i.e., false memory via spreading activation.
    • b) Depth of processing: Relates to encoding depth improving episodic memory, not specifically to intrusions of semantically related words in free recall or recognition.
    • c) Serial position effect: Concerns recall across positions in the list, not false intrusions of related words.
    • d) Visuospatial Sketchpad: A Baddeley component used to explain visuospatial tasks, not these verbal recall errors.
  • Takeaway: The intrusions are best explained by spreading activation within semantic networks, not by depth of processing, serial position, or visuospatial components.

Question 3: In Figure 2, the group of Alzheimer's patients demonstrated clearly which effect?

  • Options:
    • a) primary effect
    • b) recency effect
    • c) interference effect
    • d) continuity effect
  • Correct answer: b
  • Rationale:
    • a) Primary effect: AD data show poor recall for early items, not a primary effect; the primacy pattern is observed as better recall for early items in controls.
    • b) Recency effect: The AD pattern shows relatively better recall for the last items (recency portion) of the list compared to earlier items, indicating a recency effect in AD data.
    • c) Interference: The task used a single list; no cross-list interference is possible for this design, so an interference effect would not be evidenced here.
    • d) Continuity effect: Not applicable here; continuity is not a standard term used to describe this verbal recall context.
  • Takeaway: The AD group's recall patterns align with a recency effect driven by items still within short-term memory, while early items (primacy) are disproportionately affected.

Question 4: Which conclusion can be drawn from Figure 2 based on the recall pattern of participants without memory impairments?

  • Options:
    • a) Short-term memory is the activated part of sensory memory
    • b) Short-term memory is the activated part of long-term memory
    • c) Short-term memory and long-term memory are uniform and function similarly
    • d) Short-term memory and long-term memory represent separate memory systems
  • Correct answer: d
  • Rationale:
    • A: In Atkinson and Shiffrin's multi-store model, sensory memory feeds into short-term memory; STM is not the activated part of sensory memory.
    • B: STM is not simply an activated portion of LTM; rather, STM and LTM are distinct stores with different properties.
    • C: Serial position data show functional dissociation: primacy effects align with LTM transfer via rehearsal, while recency effects align with STM maintenance, indicating distinct systems.
    • D: The functional dissociation (primacy vs recency) supports the idea that STM and LTM are separate memory systems with different roles and capabilities.
  • Takeaway: The data illustrate a classic division between short-term/working memory and long-term memory consistent with multi-store theory.

Question 5: Is proactive interference expected in Alzheimer's patients for the word list used in the study?

  • Options:
    • A. Yes because their memory is weaker than all other groups making them most vulnerable to proactive interference.
    • B. Yes because their working memory appears to be functioning and that is where proactive interference takes place.
    • C. No, because proactive interference requires information previously stored in long-term memory, which can impede the learning of new information.
    • D. No, because proactive interference requires an intact temporal cortex and Alzheimer's patients have damage to the temporal cortex.
  • Correct answer: c
  • Rationale:
    • A: Not supported; memory weakness alone does not imply greater susceptibility to proactive interference in this context.
    • B: Proactive interference involves prior information affecting new learning, not necessarily a function of working memory alone in this context.
    • C: Proactive interference relies on information stored in long-term memory; the data suggest AD patients have impaired encoding into LTM, thus reducing the ability to experience proactive interference from prior LTM contents in this task.
    • D: The argument about temporal cortex integrity is not supported by the data; the question describes the mechanism of proactive interference rather than a strict neuroanatomical prerequisite here.
  • Takeaway: Given encoding/retention limitations in AD, proactive interference is unlikely because the necessary interference source (well-established LTM representations) may be compromised.
  • Serial position effects: primacy (beginning) and recency (end) reflect distinct memory processes.
  • Primacy effect: Items at the beginning are more likely transferred to LTM due to more rehearsal.
  • Recency effect: Items at the end are still present in STM/short-term memory at recall.
  • Atkinson–Shiffrin multi-store model: sensory memory → short-term memory (STM) → long-term memory (LTM); separate stores with distinct processes.
  • STM vs LTM independence: serial-position data (e.g., primacy vs recency) support the functional dissociation between STM and LTM.
  • False memories and spreading activation: semantically related but nonpresented items can be recalled due to activation spreading among related representations.
  • Depth of processing: deeper encoding generally improves episodic memory but does not explain false semantic intrusions.
  • Baddeley model reference: Visuospatial Sketchpad is a component of the working memory model; not directly used to explain these verbal recall/recognition errors.
  • Practical implications:
    • Memory testing in aging and disease must consider both recall and recognition tasks.
    • Serial position analyses can reveal differential preservation of memory systems in aging and disease.
    • False memories can arise from semantic associations, which has implications for eyewitness testimony and cognitive assessments.
  • Real-world relevance:
    • Distinguishing aging effects from neurodegenerative disease progression.
    • Understanding how AD disrupts encoding and retrieval to tailor interventions and cognitive strategies.
  • Ethical/clinical note:
    • Interpretations should be tempered by the AD sample limitation (age range) to avoid overgeneralization about aging vs disease-related decline.

Formulas and Notation (Examples from the Transcript)

  • Word list length: 21 words
  • Presentation rate: 3 seconds per word
  • Age groups: controls 20-39, 40-59, and 60-80; AD group 60-80
  • Conceptual relationships:
    • Primacy effect: early items gain increased likelihood of transfer to LTM via rehearsal.
    • Recency effect: end items remain in STM for recall.
  • Notation in this study is primarily descriptive and qualitative, but the relationships reflect classic memory-model equations and predictions (e.g., separable stores with different encoding/rehearsal dynamics).