What is consciousness? This question, according to Crick, is the first hurdle that needs to be tackled before one begins to pursue any knowledge about its nature. Given the importance of consciousness, and its intimate ties to the intrinsic value of our self-identity as humans, one would expect psychologists and neuroscientists to have a standard definition of what it is and its characteristics. Unfortunately, not only does such a standard definition not exist, very little effort has been made towards studying consciousness and its nature. As Crick puts it, the psychologists omit mention of it, while the neuroscientists ignore it. 

Crick traces this disinterest in studying consciousness to the rise of the behaviorist movement, which entailed studying the behavioral outputs of animals in response to various stimuli. The brain and its activities, being intermediate between stimuli input and behavioral output, was seen as a ‘black box’. Its internal inner workings were of peripheral interest, and could be ignored, as the major focus was on the predictive value of observations of behavioral output elicited by certain stimuli. Much like a computer, a lot of people do not care to know what goes on inside the CPU, or how various commands are carried out—they are only interested in the output i.e. in a computer’s function. 

Interestingly, psychologists had initially had the zeal to study consciousness—in the 19th century—through detailed systematic introspection. Unfortunately, it would be difficult to turn introspection into a science, as a lot of its results were futile. Additionally, a lot of objectivity is lost in introspective analysis, due to personal factors and biases, making it an unreliable tool. On the other hand, in neuroscience, the concept of consciousness was found to be too “philosophical” and not easily amenable to experimental study. One can just imagine the number of grant applications that were rejected because of this, and the deterrence it had on other neuroscientists willing to explore the topic. As such, in the early 20 century, it was considered taboo to talk about mental events and no one was willing to touch consciousness with a 10-foot pole. 

Nonetheless, despite these challenges, some progress had been made in both fields, enough to form some basic assumptions about what constitutes consciousness. Thanks to the rise of cognitive psychology in the 1950s and 1960s, respect to talk about mental events was somewhat restored, albeit consciousness was still rarely mentioned. Such progress, as Crick points out, was due to the works of a select number of psychologists (interestingly, he sees them as cognitive neuroscientists). 

He sketches out the three common characteristics of consciousness:

1. Consciousness is closely associated with attention. Squeeze your right hand into a fist and try to feel the pressure created by your middle finger as it digs into your palm. Do you feel that? You felt it because you paid attention to it. You may not have been feeling your feet inside your shoe until you read this sentence. You paid attention and experienced the feeling. Whatever you are aware of at that particular time, that is where your attention is directed.

2. Consciousness involves some form of memory, probably a very short-term one. Imagine a hotplate stove at its maximum. Now imagine putting your hand on the stove for hundredth of a second. You probably will not feel anything. Imagine doing it again for 5 seconds. During those 5 seconds, the acute pain you feel will be due to the sensation of heat as it is being transferred into your body. However, after 5 seconds, the pain does not immediately cease, as memory traces of it reverberate in your conscious awareness. Awareness and sensations live in short-term memory as they are being processed.  

3. Not all the operations of the brain correspond to consciousness. Try to remember your date of birth. Retrieving memory of the actual date relies on active brain processes that you are not conscious of. You do not know how you remember things, you just remember them when you put in the effort. You remember what is brought to your conscious awareness, once it is brought to your conscious awareness. This is where studies of body-language also drive this point home; people act out behaviors that they are not conscious of. 

Crick distills these three aspects of consciousness mainly from psychological works of: 

• Bernard J. Baars, who considered the close relationship between consciousness and attention. 

• Philip Johnson-Laird, who stressed the unconscious processing of the brain, and

• Ray Jackendoff, who insisted on the intimate connection between awareness and short-term memory

Keeping these characteristics in mind, he subsequently set out to outline his own approach to investigating the nature of consciousness. In collaboration with a younger colleague, Christof Koch, an associate professor of computation and neural systems at Caltech, they dispensed the notion that consciousness has to be solved by general philosophical arguments. Instead, they suggested that new experiments might throw light on these problems.

Their theoretical approach consisted of two basic assumptions: 

1.     There is something that requires a scientific explanation: since it is probable that at any one moment, some active neuronal processes in your head correlate with consciousness, while others do not. What are the differences between them? This question requires a scientific explanation.

2.     Tentatively, all different aspects of consciousness e.g. pain and visual awareness, employ a basic common mechanism, or perhaps a few such mechanisms. Understanding the mechanism of one aspect would potentially allow them to understand them all. 

With these two assumptions, they set out to study the nature of consciousness, using the visual system, as it appears easiest to study, and since humans are very visual animals. 

Blogger’s thoughts: I found it quite amusing that Crick started off the chapter searching for a scientific definition of consciousness in the field of psychology, and neuroscience, only to later suggest— when developing his own idea on how to investigate it—that it is better to avoid a precise definition because of the dangers of premature definitions. Nonetheless, the three characteristics of consciousness that he lists seem reasonable and logical. However, it seems to me that all these three characteristics can be applied to a computer or any artificial intelligence system. A computer has short-term memory (RAM), background processes that precede execution of commands, and attention given to a task being performed at a given time. Yet, we hold no conviction that computers are conscious. There seems to be a missing characteristic of consciousness that has to be taken into account, and that is, how it feels like to have an experience i.e. phenomenology. No matter how ripe your imagination, it would be difficult to imagine yourself as a computer, because largely, we believe that as machines they lack the capacity to experience anything. If you believe that computers have feelings then I find you extremely interesting as a human being. Contrarily, one does not have to be Einstein's little cousin to imagine oneself as a dog, and how that experience would feel like. Crick does, however, echo sentiments that discourage comparing computers to brains.

I suppose Crick set aside the phenomenological aspect of consciousness to save time and proceed with the actual investigation. He does list several topics that, when given attention, stall progress and result into unnecessary debates. To avoid this, he set them aside and postponed their consideration until later on. These include; a precise definition of consciousness, detailed arguments of what consciousness is, whether "lower" animals are conscious, self-consciousness etc. Will Crick's theoretical approach yield any fruitful results? Will the vision system be enough to tell us about the nature of consciousness? Let us see what Chapter 3 has for us, as Crick's adventure towards uncovering the biological correlates of consciousness takes a seemingly short detour—first he has to understand the psychology of vision.