Human Computer Interaction CSIT-400 By: Shahid Mahmood

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Agenda Human aspects of HCI Cognitive Framework Cognitive Models Cognitive psychology Cognitive Framework Cognitive Models External Cognition Distributed Congnition

Scenario: Car drive

Cognition How the human think It is the process by which we became acquainted with things or in other words gain knowledge Whatever human do some sort of cognition might have been happening at the back end

Modes of Cognition Experiential Cognition Reflective Cognition

Experiential Cognition In ‘experiential Cognition’ we perceive act and react events around us effortlessly. E.g, Car drive Less mental effort Initially require some learning

Reflective Cognition In reflective Cognition some mental exertion is required. E.g., writing an article or poem OR drawing a picture.

Human Information Processing Recognizing something means processing the information gained about that thing in your mind. This depicts the notion that human mind works like a processor

Human Information Processing Model (simple format) Encoding Comparison Response Selection Response Execution

Human Information Processing Model Encoding: Information from environment is encoded in some kind of internal representation Comparison: Internal representation is compared with memorized representations Response Selection: Concerned with deciding on a response to the encoded stimulus Response Execution: Organizing response and necessary action

Human Information Processing Model (Extended) Encoding Comparison Attention Memory Response Selection Response Execution

Human Processor Model - Perceptual System It helps us to conceptualize the human behavior and to model human processor It is composed of three different systems, each of which having two components i.e. a processor component and a memory component: - Perceptual System - Motor System - Cognitive System This measures the qualitative aspects of human performance

GOMS Model Goals Operators Methods Selection Rules This measures the quantitative aspects of human performance

Basic purpose of Cognitive framework The basic purpose of Cognitive framework is to understand and predict human behavior so that we can predict the user behavior on use of computer/ computer-based system

Computational Approach Adopts computer metaphor as a theoretical framework What is involved when information is processed rather than how and when Conceptualization of the goals planning and action in terms of task performance is done

Connectionist Approach Also known as Neural network or Parallel distributed processing approach where cognition is presented at the level of neural network consisting of interconnected nodes Cognition process is viewed as activation of nodes in the neural networks and the connection between them Rejects computer metaphor Adopts brain metaphor

Shortcomings of behavior and cognitive approaches They do not represent the real world (considering the context) which neglect isolation They represent a controlled environment instead of actual They are very simple in nature and ignore complexity Any prediction done on their bases could be tragically wrong

External Cognition framework It has got three different elements: Externalizing to reduce memory load (telephone diary) Computational Offloading (Calculator) Annotating and Cognitive tracing (Modify representation to reflect changes that are taking place by Annotating (cross| underline) and cognitive tracing (re-arrange for better comprehension)). For example In computer we develop graphical user interfaces for various web pages

Distributed Cognition framework The goal is to provide explanation to conceptualize cognitive activities (attention, thinking, learning) with in the work context Cognitive activities are distributed among external technology and other people with in the context Information changes its states (verbal, mental, manifested in a device)

Questions?