🖥️Human-Computer Interaction Unit 2 – Human Cognition and Perception Basics

Key Concepts and Terminology

• Cognition encompasses mental processes involved in acquiring, processing, and using information
• Perception involves interpreting sensory information to understand the environment
• Attention refers to selectively focusing on specific stimuli while ignoring others
• Memory consists of encoding, storing, and retrieving information
  • Sensory memory holds information briefly before it is processed or lost
  • Short-term memory (working memory) temporarily stores and manipulates information
  • Long-term memory stores information for extended periods
• Cognitive load refers to the mental effort required to process information
• Mental models are internal representations of how a system or process works
• Affordances are properties of an object that suggest how it can be used (door handle)
• Signifiers are visual cues that communicate the purpose or function of an element (play button icon)

Sensory Processing and Perception

• Sensory processing involves receiving and interpreting information from the senses
• Vision is the dominant sense in human perception and plays a crucial role in interface design
  • Visual hierarchy guides attention through the use of size, color, and placement
  • Gestalt principles describe how the brain organizes visual elements into meaningful patterns (proximity, similarity)
• Auditory perception involves interpreting sound, including pitch, volume, and location
  • Auditory cues can convey information and provide feedback (alerts, notifications)
• Haptic perception involves the sense of touch and can enhance user experience (vibrations, textures)
• Perception is influenced by prior knowledge, expectations, and context
• Perceptual organization principles explain how the brain groups and interprets sensory information
  • Figure-ground organization distinguishes between foreground and background elements
  • Proximity principle suggests that elements close together are perceived as related

Attention and Memory

• Attention is the process of selectively focusing on specific information while ignoring other stimuli
• Selective attention allows us to prioritize and process relevant information
  • Bottom-up attention is driven by salient stimuli in the environment (bright colors, sudden movements)
  • Top-down attention is guided by goals, knowledge, and expectations
• Divided attention involves simultaneously processing multiple stimuli or tasks
  • Multitasking can lead to decreased performance and increased errors
• Memory plays a crucial role in learning, problem-solving, and decision-making
• Working memory has a limited capacity and can hold approximately 7 ± 2 items
• Chunking involves grouping related information into meaningful units to enhance memory
• Long-term memory has an extensive capacity and can store information for extended periods
  • Retrieval cues help access stored information (associations, context)
• Interference occurs when similar or competing information hinders memory retrieval

Decision Making and Problem Solving

• Decision-making involves choosing between alternatives based on available information and goals
• Heuristics are mental shortcuts that simplify decision-making but can lead to biases
  • Availability heuristic relies on easily accessible information to make judgments
  • Representativeness heuristic judges the likelihood of an event based on its similarity to a typical case
• Biases influence decision-making and can lead to suboptimal choices
  • Confirmation bias seeks information that confirms existing beliefs while ignoring contradictory evidence
  • Anchoring bias relies heavily on the first piece of information encountered
• Problem-solving involves finding solutions to complex or novel situations
• Analogical reasoning uses knowledge from a familiar domain to solve problems in a new domain
• Mental models guide problem-solving by providing a simplified representation of a system or process
• Insight involves a sudden realization or understanding of a problem's solution

Cognitive Load and Information Processing

• Cognitive load refers to the mental effort required to process information
• Intrinsic cognitive load is inherent to the complexity of the information itself
• Extraneous cognitive load is imposed by the presentation or design of the information
• Germane cognitive load is beneficial and contributes to learning and skill acquisition
• Information processing involves perceiving, encoding, storing, and retrieving information
• Attention acts as a filter, selectively processing information and allocating mental resources
• Automaticity develops with practice, allowing tasks to be performed with minimal cognitive effort
• Cognitive overload occurs when the demands placed on cognitive resources exceed available capacity
  • Overload can lead to decreased performance, errors, and frustration

Individual Differences in Cognition

• Cognitive abilities vary among individuals, influencing performance and user experience
• Working memory capacity differs between individuals and affects the ability to process and store information
• Cognitive style refers to an individual's preferred way of processing information (visual, verbal)
• Prior knowledge and expertise influence how individuals perceive and interact with interfaces
  • Experts have well-developed mental models and can process information more efficiently
  • Novices require more guidance and support to navigate unfamiliar interfaces
• Age-related changes in cognition can impact perception, attention, and memory
  • Older adults may require larger text, higher contrast, and simplified interfaces
• Cultural differences in cognition can influence information processing and decision-making
  • Collectivistic cultures may prioritize group harmony and context over individual preferences

Implications for Interface Design

• Understanding human cognition and perception is essential for designing effective interfaces
• Minimize cognitive load by presenting information clearly and concisely
  • Use visual hierarchy, grouping, and white space to guide attention
  • Provide clear labels, instructions, and feedback to support understanding
• Leverage perceptual principles to create intuitive and visually appealing designs
  • Use color, contrast, and typography to convey meaning and importance
  • Apply Gestalt principles to organize and structure information
• Consider individual differences and provide flexibility in interface design
  • Offer customization options for font size, color schemes, and layout
  • Provide multiple ways to access and interact with content (keyboard, mouse, touch)
• Design for error prevention and recovery to minimize frustration and cognitive strain
  • Provide clear error messages and suggestions for resolving issues
  • Allow for undo/redo functionality and confirm destructive actions
• Conduct user research and usability testing to validate design decisions and identify areas for improvement

Real-World Applications and Examples

• E-commerce websites use visual hierarchy and persuasive design principles to guide users through the purchasing process (Amazon)
• Navigation systems in cars minimize cognitive load by providing clear directions and reducing distractions (Google Maps)
• Educational software adapts to individual learning styles and provides personalized feedback (Duolingo)
• Accessibility features in operating systems accommodate users with varying cognitive abilities (Windows High Contrast mode)
• Social media platforms leverage attention-grabbing techniques to keep users engaged (infinite scroll, notifications)
• Data visualization tools use perceptual principles to communicate complex information effectively (Tableau)
• Gaming interfaces optimize for user experience and minimize cognitive load during fast-paced gameplay (Fortnite)
• Productivity applications use intuitive layouts and clear signifiers to support efficient task completion (Microsoft Office)