What are Human Information Processing Systems?
- Hereby referred to as HIPS, the human information processing system is an automatic system that a person uses to interpret information and react.
- It is normally comprised of inputs, processes (which can be sensory, central and motor), and outputs.
- The analysis of the human information processing system requires a designer to critically analyze a range of causes and effects to identify where a potential breakdown could occur and the effect it may have.
HIPS Model
- The processing flow of the system can be described as a flowchart model.
- In the model the situation occurs step by step, starting with the input.
- While somewhat outdated, the model can still accurately explain most situations.
- The model is described as follows.
Input
- The relevant outside stimulus or stimuli.
Example
- A red traffic light when driving.
Sensory Processes
- One of the five sensory processes that observe and interpret the stimulus.
- Can be smell, vision, taste, hearing or touch.
Example
- You see the traffic light.
Central Process
- The brain, which is the central processing unit, examines the information observed by the sensory processes.
- The brain then selects a specific motor response.
Example
- Your brain remembers traffic rules and understands that you should stop. Thus it signals to your leg muscles to press down on the brakes.
Motor Processes
- The motor processes are the activity of muscles in your body.
Example
- Your leg muscles move your foot to press down on the brake.
Output
- The output is the result of the motor processes.
Example
- The car stops at the traffic light.
Environmental Factors
- Environmental factors are a set of psychological factors that can affect the performance of an individual that come from the environment that the individual is situated.
- Environmental factors can cause breakdowns, which disrupt the whole system.
Possible Factors
- Temperature
- E.g. too warm and you get sleepy and less alert , too cold and you become more alert.
- Next time you are on a long haul flight note the temperature fluctuations while flying.
- Sound
- E.g. too loud noise which can be distracting or even cause harm, high pitched or repetitive on/off noises also become distracting.
- Lighting
- E.g. when it is too dimmed it is hard to see things, you need to get closer or it strains the eyes.
- Natural and fluorescent light can affect people's eyes in different ways.
- Lighting can also affect mood, which might affect alertness and central processing.
- Air quality
- E.g. excess dust or other pollutants could cause people to find it hard to breathe, maybe cough, etc.
- Certain essential or aroma oils are said to improve alertness
- Smell
- E.g. bad smells will draw one's attention away, as would the smell of a hot apple pie.
- Color
- Certain shades and values of color contrast against one another, making the object "pop out".
- Some colors are naturally attention-grabbing, such as red.
- This can be useful to make something easier to notice.
- E.g. a red traffic light over a black traffic light box makes it very noticeable.
Examples
- Consider the same example from the HIPS model, but now it is dark and raining. It might become difficult to see in the dark, causing a delay in your reaction to the traffic light.
- This might cause you to not be able to stop in time and go over the zebra crossing.
- Environmental factors can affect all of the processes.
- Sensory process: your eyes don’t register the red light (on time), due to speeding, lack of concentration, block of eyesight, tiredness, overheating etc.
- Central process: your brains do not send the (right) signals to your muscles, due to panic, wrong judgement, amnesia etc.
- Motor process: your foot does not hit the break (on time), due to weak muscles, paralysis etc.
Concepts
Alertness
- Alertness is the level of vigilance, readiness or caution of an individual.
- When alert, individuals are quicker to react, and tend to be more attentive.
Human Error
- Mistakes made by users, some of which can result in catastrophic consequences for people, property and the environment, as they are considered key contributors to major accidents.
Workplace Performance
- Performance in the working environment is affected by a variety of factors.
- These factors can be considered to maximize performance of a user in a role and reduce the risk of accidents. They can be categorized as follows.
Management
- Such as policies and safety education.
Physical Environment
- Such as noise, temperature, pollutants, trip hazards and signage.
Equipment Design
- Such as controls, visibility, hazards, warnings and safety guards.
The Nature of the Job
- Natural characteristics of the job such as repetitiveness, mental or physical workload, force and pressure.
Social Environment
- Such as social groups and morale in the workplace.
The Worker
- Features of the worker themselves.
- Such as personal ability, alertness, age and fatigue.
Example
Thermal comfort describes a person’s psychological state of mind.
It involves a range of environmental factors:
- air temperature
- the heat radiating from the sun, fires and other heat sources
- air velocity (still air makes people feel stuffy, moving air increases heat loss)
- humidity
- personal factors (clothing and metabolic rate).
In an office environment, where a number of people work together, the thermal environment should satisfy the majority of the people.
Thermal comfort is not measured by air temperature (quantitative), but by the number of people complaining (qualitative) of thermal discomfort.
Sensorial Design
- Sensorial design can appeal to the senses, either by depriving them of distractions or by stimulating them positively.
- It aims to improve what users experience when they use the product.
- It can be used to standardize the experience, by limiting outside factors.