Human Computer Interaction-module 1.pptx

Human Computer Interaction-module 1.pptx

1. Human-Computer interaction Module 1 Computers and Human Behavior

2. Introduction to HCI Human–Computer Interaction (HCI) is the study of how people use and experience digital systems and devices in their daily lives. Its aim is to design technology that is easy to use, efficient in achieving goals, and pleasant or rewarding to interact with. Combines knowledge of human psychology (thinking, feeling, behaving) with engineering and design principles. Effective HCI reduces mistakes, prevents frustration, and improves overall satisfaction in using technology. Engineers, designers, and psychologists work together to ensure systems meet both functional needs and human limitations.

3. The Cognitive Lens in HCI Focuses on the  thinking processes  involved when users interact with digital systems — such as attention, memory, problem-solving, and decision-making. Human Information Processor Model: users receive information through senses, process it in the mind, and respond with actions; each stage has limits that designers must respect. GOMS Model: breaks tasks down into Goals (end targets), Operators (actions), Methods (steps), and Selection rules (how one method is chosen over another) — useful for predicting task efficiency. Designs should lower mental effort by presenting information clearly, reducing unnecessary steps, and supporting recognition over recall. Example: intuitive navigation menus that match natural thought processes.

4. Emotional Lens in HCI Emotional reactions strongly shape whether users continue to use a system and how satisfied they feel. Norman’s Three Levels of Emotional Design: Visceral : First impressions and sensory impact (look, feel, sound). Behavioral : Quality of the actual use experience — ease, control, and responsiveness. Reflective : Personal meaning and memories after use, shaping long-term opinions. Positive emotions can increase creativity, learning, and engagement, while negative emotions can cause avoidance or errors. Affective Computing: technology that senses a user’s feelings (through language, behavior, or sensors) and adapts responses accordingly — making systems more supportive and human-like.

5. Behavioral Lens in HCI Looks at  observable actions and patterns  of use — what people actually do rather than what they say they do. Helps identify common navigation paths, frequent mistakes, and habits that form when using a system. Designers use this data to improve or simplify interfaces over time through iterative testing. Can include ‘behavioral nudges’ — subtle interface cues that encourage beneficial actions, like wellness reminders or reward progress trackers. Example: a language learning app that celebrates daily usage streaks to encourage habit formation.

6. Integrating the lenses Real-world design benefits from considering cognition, emotion, and behavior together rather than separately. Cognitive design ensures the system is mentally easy to use, emotional design ensures it is engaging and appealing, and behavioral design ensures it fits naturally into user routines. Adaptive systems can change based on what the user knows (cognitive), how they feel (emotional), and what they typically do (behavioral). Example: an educational platform that adjusts difficulty based on performance, provides encouraging feedback when the learner struggles, and tracks learning habits to recommend optimal study times.

7. Attention in the Digital Age Attention is the ability to focus on relevant information while ignoring distractions — crucial for effective interaction with technology. Bottleneck Models explain that our brain can only deeply process a limited number of inputs at a time. Early Selection : the brain filters information before processing it deeply. Late Selection : most inputs are processed briefly, but only some reach conscious thought or action. In the digital world, constant notifications fragment attention into “continuous partial attention,” reducing focus. Good interface design can direct attention to key information and reduce unnecessary cognitive interruptions.

8.  Memory and Usability Human memory in HCI includes: Working Memory: short-term, actively used information — extremely limited and prone to overload. Long-Term Memory: stored experiences and learned information — accessed when recognition or recall is required. Poor design can overload working memory, leading to frustration and mistakes. Usability improves when systems ‘offload’ memory demands — for example, by using clear labels, recognizable icons, and grouping related options together. Progressive disclosure — showing information gradually instead of all at once — helps users learn and retain information.

9. Multitasking Effects Most so-called multitasking online is actually  rapid switching  between tasks, which reduces speed and increases errors. Performing two demanding tasks at once strains working memory and attention capacity. Studies show that while people can combine a routine task with a simple new task, performance drops sharply when both require focus or problem-solving. Frequent switching between device notifications, messages, and main tasks reduces comprehension and recall. Digital systems perform best for users when they allow or encourage focused activity rather than constant switching.