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Introduction

We receive information from the world around us through our senses: sight, hearing, touch, smell and taste. When flying an aircraft the pilot must observe and react to events both in the cockpit and in the environment outside the aircraft. The information from our senses must be interpreted in order to make decisions and take actions to ensure the safe path of the aircraft at all times.

In this chapter we will lay out the basic system by which we receive and process information in order to make decisions and recognize where errors in the system may be the cause of accidents. At the end of this chapter the learning process is briefly discussed.

Basic Information Processing

We know that the process of thought and decision making is achieved by electrochemical currents within the brain, but it is not possible to precisely relate each stage of the processes to a particular anatomical structure in the brain. We need to build a functional model of the various stages of our reasoning. These are:

•Detection (information is received).

•Perception.

•Decisions are taken.

•Action (responses are selected and executed).

•Feedback.

This model is of great importance when errors are considered. We can determine if the errors result from a failure of perception, a failure of memory, or in spite of having correctly interpreted the information, we have failed to take the correct action. The functional model also helps in understanding other factors, such as stress, that may influence our performance. The model is based on a series of stages that occur between receiving information and a response being made.

Figure 8.1, on the next page, shows a typical functional model. The various sections of the model will be discussed both individually and as part of the full mechanism.

Information Processing, Human Error and the Learning Process 8

Process Learning the and Error Human Processing, Information 8

Figure 8.1 A functional model of information processing

“Bottom-up” and “Top-down” Processing

An important concept of information processing is “bottom-up/top-down” doctrine. Very many mental activities like remembering, perceiving and problem solving involve a combination of information from two sources:

•Incoming information from the outside world (i.e. the input received by the sense organs) and

•The information already stored in memory (i.e. prior knowledge derived from past experience).

The analysis of the sensory information coming in from the outside is known as “bottom-up”or data-driven processing because it relies on the data received via the senses.

The sensory information is often incomplete or ambiguous, but the information already stored in the memory in the form of prior knowledge influences our expectations and helps us to interpret the current input. This influence of prior knowledge is known as “top-down” or conceptually-driven processing.

In practice, the two sorts of processing operate in combination. For example, “bottom-up” processes may yield sensory information about a moving black shape of medium size and having a smooth texture. “Top-down” processes based on already stored knowledge enable this to be identified as a Labrador dog. The “top-down” processes interact with the information provided by the “bottom-up” processes. This is sometimes known as interactive processing.