Basic Cognitive Functions

(9-28-16)

Information processing

information-processing approach uses a computer metaphor (caution about analogies/metaphors/models): information is imputed, transformed, coded, stored, acted on
information-processing model rests on three assumptions (Neisser, 1976)
- 1. people are active participants in the process
  - information is transformed based on what you already know about it
- 2. both quantitative (how much info is remembered) and qualitative (what kinds of info are remembered) can be studied
  - there are age difference in both how much and what types of data are remembered best under various conditions
- 3. information is processed through a series of stages/processes
  - brief sensory memory and attention
  - active processing that transfers data into longer term storage
  - retrieval mechanisms
  - decision making/planning/problem solving mechanisms
Sensory stimuli/experience
Sensory memory: immediate, almost eidetic representation (perception) in brain
- large capacity, very short term representation
Speed of processing: how quickly and efficiently these early steps in information processing are completed (Cavanaugh & Blanchard-Fields, 2006, p. 189)
Information processing changes with age
- reaction times slow as we age
  - wide individual differences
  - degree of decrement usually small (until very advanced age)
  - very robust finding
- Why do we slow with advancing age?
  - general slowing hypothesis: general decline in information processing speed in aging brain
    - Timothy Salthouse (1996, 2000; Kail & Salthouse, 1994): processing speed theory of adult age differences in cognition (fluid intelligence)
    - much experimental date supports this position, although there remains questions as to whether cognitive speed can account for all individual differences (Bors & Forrin, 1995)
    - changes in white matter (axional connections) may be one contributing factor (Ylikoski et. al, 1993) to changes in attention and processing speed
  - age-complexity hypothesis: age differences increase with task complexity
    - Cerella, Poon, & Williams (1980) published influential study suggesting that cognitive slowing differences between younger and older adults were associated with complexity of task
  - methodological issues regain a challenge to sorting out our clearest answers to these questions

Attention

attention governs information flow within other cognitive domains
- attentional processes facilitate, enhance, or inhibit other cognitive processes
- attention leads to orientation toward particular stimuli or responses (and away from others)
- There can be compertition in our brains between two different attentional processes:
  - Bottom-Up Attention: rapid, demanding, not consciously controlled; survival oriented; almost instantly captures our attention; automatically driven by sensory stimuli and contextual cues
  - Top Down Attention: effortful, deliberate, conscious: when we direct our focus on a work task; top-down attention reflects our setting our objectives and focusing on them
  - “Top-down and bottom up attentions are both essential to survival, and so is the balance between them. If we had no top-down attention, we couldn’t focus on important goals. But without bottom-up, we wouldn’t be alerted to new stimuli, including danger. Imagine a caveman being so focused on building a fire that he never heard the lion coming through the bushes.” (Richtel, 2014,p. 106)
- sensory selective attention: selection of salient sensory information for further processing
- sustained attention (concentration): maintenance of attention over time to stimuli or task
- freedom from distraction: inhibition of competing signals
- Four components of attention (Cohen, Malloy, Jenkins, Paul, 2006)
  - SENSORY SELECTIVE ATTENTION: tends to be automatic
  - filtering: sensitivity or preferences guild perceptual processes
  - enhancement: attentional readiness and expectancy increases focus
  - disengagement: attentional shift requires reallocation and requires processing resources
- RESONSE SELECTION AND CONTROL: (intention): facilitation of action through selective attention and control of behavioral responding; tend to be effortfull
  - readiness: mediated by arousal and reinforcement history
  - expectancy: that a response will be needed at a particular time
  - anticipatory response: preparatory responses
  - executive functions are linked to response selection
    - intention: processes leading to response set and preparation
    - initiation: processes that start a response
    - generative capacity: processes that facilitate production of a response
    - persistence: processes that enable sustained responding
    - inhibition: processes that prevent or enable cessation of the response
    - switching: processes that enable a shift from one response to another
- ATTENTIONAL CAPACITY AND FOCUS
  - focused attention controls the intensity and scope of attentional allocation, thus the cognitive resources directed at a particular task
  - focus is also a function (is influenced/controlled by or limited by) of processing capacity
  - attention capacity reflects both motivational and inherent capacity of the system (brain)
    - motivational (state or situational variables)
      - arousal
      - reinforcement value
      - expectation of reinforcement
    - factors intrinsic to the individual (trait variable)
      - individual differences in mental abilities
      - significant variability across people
  - automatic versus controlled processing
    - attention may be elicited automatically by some environmental cues; and, once learned, some behaviors require minimal attentional capacity
    - automaticity refers to capacity to attend to and perform certain operation with minimal effort and without need for active direction
    - intentional focus to task usually results in reduced automaticity
    - once learned a task requires less working memory and reduced controlled effortful processing (conscious)
    - effortful processing, which requires more attentional capacity, usually shows greater age effects in testing results (Hertzog, 2008)
- SUSTAINED ATTENTION (VIGILANCE) (vigilance)
  - maintenance of optimal performance over time requires sustained attention
  - vigilance is a form of sustained attention in which there need for a high level of anticipatory readiness for low-probability targets or stimulus events (flight controllers, standing guard, fishing)
  - sustained attention is a function of task duration (any task can be prolonged until failure occurs), target-distractor ratio (more difficult with rare target events), effortfulness of task (demand for high level of focus are more difficulty to sustain), organism characteristics (arousal, motivation, capacity)
Attentional changes with age
- attentional performances/capabilities decline with advancing age
  - wide individual differences
  - very robust finding
- Why does attentional capacity change with age?
  - attentional resources theory: aging reduces available cognitive resources
  - inhibitory deficit hypothesis: aging rduces ability to tune out irrelevant information
  - context processing deficiency hypothesis: aging reduces the ability to tke context into account
- Limits of our attention
- the invisible gorilla tapes
- texting and driving

Memories

Memory: the recall of things past
- encoding (learning): how information is entered into the memory system
- storage: how information is kept or represented in memory
- retrieval: how information is accessed or gotten out of memory when needed
Three-stage mode lof memory
- Three-stage model of memory
  - Sensory storage: sensory stores or buffers [less than a second to seconds]
    - forgetting results from: decays
  - Short term memory: conscous awareness of recently perceived events [seconds to minutes; up to 30 seconds]
    - requires attention to shift from sensory buffer
    - forgetting results from: displacement
    - limited capacity: G.A. Miller (1956) & “the magic number seven plus or minus two”
    - some investigators devide short-term memory into “primary memory” [passive storage in same form it was received in] and “working memory [active processing of information]
  - Long term memory: evants that have left consciousness but can be retrieved [minutes to hours to decades]
    - requires rehearsal and elaboration to shift from short term memory
    - forgetting results from: interference
Working memory: active process which houses and operates on information to deal with a need or challenge/problem (making a decision, learning new information, directing an action); memory tasks which require working with a lot of information at once; active and simultaneous processing and storing of information [some authors include this as part of short term memory]
Baddeley’s (2001) model of working memory:

Long-term memories
- Explicit Memory (declarative memory): conscious memories, you know and know that you know
  - episodic memory: memory for past events
  - semantic memory: language coded memories–word knowledge, facts, ideas
    - demand memory (point retrival): word finding, name finding
  - remote memory: memories from the distant past
  - source memory: recall of contextual information; how did you learn, how do you know this?
  - autobiographical memory: recollection of your personal history
  - prospective memory: recall of events which need to be performed in the future/recall in the present of actions you decided to perform in the past
  - flashbulb memory: recall of dramatic/highly emotional or meaningful events from your life
  - short-term memory: recall of information from the near past
  - visual-spatial or nonverbal memory: recognition or duplication of designs, movements, spatial orientations
- Implicit Memory (non-declarative memory): retrieval of information without conscious or intentional recollection
  - procedural memory: remembering how to perform a skill you have learned
  - priming effects: prior exposure to a stimulus makes it a more likely response (and may underlie some unconscious emotional responses)
    - sentence completion tasks, such as: “Say the first word that comes to mind to complete this word: ‘con____'”; prior exposure to material showing the word “contest” versus “contract” influences the likelihood of the responses (Zacks et al., 2000)
- Assessment of memory
  - recall: retrieval of previously learned information “without hints or cues”: “What is the capital of . . . . ?”, “What is that person’s name?”
    - What counts as “hints or cues”
    - task characteristics
    - contextual information
  - recognition: selection of the previously learned information from among a group: “Aren’t you in my Adult Development class?”, “What brand of butter was it that my partner asked me to bring home for dinner?”
    - distractors or foils
    - context again
  - performance effects: “Lets see if I remember how to do this.”
Memory changes with age
- some memory performances decline more with advancing age, some memory performances are relative stable (until very advanced age and/or dementing disease)
  - relative “hold” memories
    - semantic memory (but younger subjects may tend to remember more details)
    - procedural memory
    - implicit memory (maybe, some conflict in literature)
    - autobiographical memory (events but not sequence)
    - flashbulb memory (but even these recollections can be influenced)
  - relative “don’t hold” memories
    - episodic memory
    - source memory (often lost)
    - point ret rival (visual naming, immediate situational demands)
    - prospective memory
- Why do memory performances change (or not change) with age?
  - attentional changes (storage problems–learning problems)
  - learning changes (storage problems–learning problems)
    - shift to less efficient encoding strategies (conceptual grouping, rehearsal)
  - retrieval changes (interference problems)
    - false memories
  - expectance/belief changes (psychological issues): “memory controllability”–beliefs about our memory and/or aging effects on memory
    - “I don’t think you can, I don’t think you can, I don’t think you can . . . . you can’t!”
    - “I don’t think I can, I don’t think I can, I don’t think I can . . . . I can’t!”
- Enhancement of memory
  - trait and state aspects of learning and recall
    - trait: individual differences
    - trait: modestly stable
    - trait: clearly influenced by general health, exercise, diet, mental activity
    - state: influenced by motivation, arousal, current health, emotional state (anxiety, depression)
    - state: influenced by expectation, belief, social variables (stereotype thre
  - systematic training
    - programs designed to improve memory in older adults do produce improved memory performance
      - both objective memory performance (.73 standard deviations: greater than rest [.38] or placebo [.37], meta-analysis by Verhaeghen, Marcoen, & Goosens (1992)
      - and person’s subjective evaluation (approximately .2 standard deviations, meta-analysis by Floyd & Scogin (1997)
    - no one type of training is superior (Verhaghen et al., 1992; Rasmusson et al., 1999)
      - often use visual association with locations (loci method) or words (peg word method)
      - these techniques have been used by orators since ancient Roma (and possibly before)
      - no evidence that “general purpose memory” improved by these training methods; they work by teaching strategies used for remembering and retrieving specific information, not by affecting general processing speed or neuroplasticity

Long-Term Memory

Declarative (Explicit)
- conscious recall of facts & events
- based on context of experience
- requires representational storage
  - medial temporal lobe
  - hippocampal system
Non-Declarative (Implicit)
- collection of abilities (action system)
- unconscious, inflexible, outside of awareness
- Skills & Habits
  - striatum
- Priming
  - neocortex
- Classical Conditioning (Respondent)
- emotional responses
  - amygdala
- skeletal responses
  - cerebellum
- Nonassociative learning
  - reflex pathways