Information Processing, Memory, and Performance Under Stress: Decision Stage 2

Information Processing Model

Overview of the Information Processing Model

The information processing model describes how humans perceive, interpret, and respond to stimuli. It is a foundational concept in cognitive psychology and motor control, outlining the stages through which information passes before a response is generated.

• Stages: Stimulus identification, response selection, and movement programming.

• Factors influencing speed:

  1. Number of stimulus-response alternatives

  2. Stimulus-response compatibility

  3. Population stereotypes

  4. Amount of practice

• Anticipation: Can hasten the speed of response.

• Memory: Affects the choice of response to stimuli.

Memory

Definition and Components of Memory

Memory is the process of retaining information over time. It plays a critical role in determining how we respond to stimuli and is divided into three main components:

• Short-term sensory store (STSS)

• Short-term memory (STM)

• Long-term memory (LTM)

Stages of Memory

Memory processing involves the transfer of information through different stages, each with its own characteristics and limitations.

• Sensory memory: Receives sensory input; unattended information is lost.

• Short-term memory: Information attended to is transferred here; unrehearsed information is lost.

• Long-term memory: Information encoded from STM is stored here; some information may be lost over time.

Processes: Attention, maintenance rehearsal, encoding, and retrieval.

Short-term Sensory Store (STSS)

• Stores vast amounts of sensory information (auditory, visual, kinesthetic) briefly.

• Duration: Few seconds for auditory, 250 ms for visual information.

Sperling Experiment (1960)

The Sperling experiment demonstrated the capacity and duration of visual sensory memory (iconic memory). Participants could recall more items when cued immediately after presentation, indicating a large but brief sensory store.

Short-term Memory (STM)

• Temporary holding place for information (e.g., a phone number given verbally).

• Without rehearsal, information is lost quickly (about 30 seconds).

• Attention and rehearsal (encoding) help retain information in STM.

Long-term Memory (LTM)

• Stores well-learned information collected over a lifetime (unlimited duration).

• Information is consolidated from STM to LTM through effortful processing.

• Learning implies information has been transferred from STM to LTM.

Limitations in Stimulus Identification

Parallel Processing, Inattention Blindness, and Sustained Attention

• Parallel processing: Ability to process multiple stimuli simultaneously.

• Inattention blindness: Failure to notice unexpected stimuli when attention is focused elsewhere.

• Sustained attention: Ability to maintain focus on relevant stimuli over extended periods. Vigilance decreases over time due to factors such as motivation, arousal, fatigue, and environmental conditions (e.g., temperature, noise).

Limitations in Response Selection

Controlled vs. Automatic Processing

Response selection can be limited by the type of processing involved:

Automatic Processing (System 1)	Controlled Processing (System 2)
Fast Effortless High capacity Nonverbal Implicit/Associative Parallel processing	Slow Effort required Limited capacity Involves language Explicit Logical/procedural Serial processing
Examples: Answer to 2+2=? Read words on billboards Drive a car on an empty road Orient to sudden noise Detect hostility in a voice	Examples: Focus on clowns at a circus Count occurrences of 'a' on a slide Fill out a tax form Wait for starter's pistol Park in a narrow space

Automaticity is developed through extensive practice, especially under consistent conditions. While fast and efficient, automatic processing can lead to errors if the environment changes unexpectedly.

Response Selection and Distraction

• Driving: Distraction (e.g., using a cell phone) affects response selection more than movement programming, as the cognitive load of conversation interferes with selecting appropriate responses.

• Walking/Texting: Texting while walking slows response selection and increases risk (e.g., failing to look both ways).

Limitations in Movement Programming

Psychological Refractory Period (PRP)

The psychological refractory period is the delay in responding to the second of two closely spaced stimuli. If a second stimulus occurs within 50–200 ms after the first, the response to the second is delayed by at least 100 ms in addition to normal reaction time (RT).

• The motor system processes the first stimulus and generates the first response before the second can be processed.

Double Stimulation Paradigm

• Subjects respond to two stimuli presented closely in time (stimulus-onset asynchrony, SOA).

• Delays occur due to interference in programming both responses rapidly.

• Very short SOAs (<40 ms) can cause grouping, where both responses are produced simultaneously.

Timing Considerations of the PRP

• If $S_2 < 50$ ms, $S_1$ and $S_2$ are treated simultaneously.

• If $50 < S_2 < 200$ ms, $RT$ for $S_2 = 1\ RT + 100$ ms.

• If $S_2 > 200$ ms, $RT$ for $S_2 = 1\ RT$.

The Information Processing Bottleneck

When two stimuli are presented in close succession, the response programming stage acts as a bottleneck, forcing the second stimulus to wait until the first is processed. This results in delayed responses and increased reaction times.

Performance Under Conditions of Increased Stress

Arousal, Perceptual Narrowing, and Choking Under Pressure

• Arousal: Physiological and psychological state of alertness that affects performance.

• Perceptual narrowing: Under stress, the perceptual field shrinks, focusing attention on the most relevant stimuli but potentially missing other important cues.

• Choking under pressure: Occurs when performers fail to adapt to changing situations, often due to increased anxiety or reward, leading to performance failure.

Inverted-U Principle

The Inverted-U Principle describes the relationship between arousal and performance:

• Low arousal: Wide attentional focus, but may pick up irrelevant information.

• High arousal: Narrowed focus, fewer stimuli detected, slower reaction time.

• Optimal arousal: Focus is narrow enough to exclude distractions but wide enough to gather important cues.

Variations of the Inverted-U Principle

• Task differences and individual differences (e.g., excitability) can shift the optimal point of arousal for best performance.

• Complex tasks or individuals who function best under calm conditions may have a lower optimal arousal point.

• Simple tasks or individuals who thrive under pressure may have a higher optimal arousal point.

Perceptual Narrowing

• Perceptual field shrinks under stress with high arousal.

• Allows focus on immediately relevant stimuli but may exclude other important information.

Choking Under Pressure

• Occurs when performers change their routine or fail to adapt, resulting in failed performance.

• Possibility of increased rewards leads to performance failure (inverted-U relationship).

• Attentional control theory of anxiety: Anxiety reduces attention to the current goal in the presence of threatening stimuli (Eysenck et al., 2007).

• Neural mechanisms: High reward acts as a distraction to motor preparation, involving reward and motor preparation brain structures.

Summary

• Memory, attention, and perceptual processes all affect performance at different stages of the information processing pipeline for movement control.

Additional info: This summary integrates foundational concepts from cognitive psychology, including memory systems, attention, and the effects of stress on performance, as well as classic experimental paradigms (e.g., Sperling, PRP) and theoretical models (e.g., Inverted-U Principle).