There is clearly a relation between consciousness and planned action, this has been recognised since the time of Aristotle. Many of our plans are conscious; the execution of those plans often requires conscious activity, and much of our conscious activity is involved in the goal-directed control of action. In so far as he attempts to explain the phylogenetic evolution of consciousness, Bridgeman seems to be looking in the right place; an account of the evolution of consciousness that emphasizes its connection to behavioral consequences. The assimilation of communication to planned behavior more generally would also seem to be promising. However, there are a number of reasons to believe that the connections that lie at the crux of Bridgeman's account are less straightforward than he caimss.
1.2 The obscurity of the concept of consciousness is evident. Planned action would seem prima facie to be a far more straightforward notion. However, I believe that the failure to analyze it at least into planning, on the one hand, and the execution of plans, on the other, undermines Bridgeman's (1992) attempt to explain aspects of consciousness by means of a psychology based on plans.
1.3 Bridgeman (1992) variously (1) identifies consciousness and the execution of plans and (2) describes a causal relation between them. In his Abstract, Bridgeman writes, "Consciousness IS the operation of the plan-executing mechanism" (emphasis added); Throughout the target article, however, he suggests that consciousness results from the operation of such a mechanism (e.g., sections 2.8, 2.9, and 4.1).
1.4 Bridgeman himself notes the distinction between (as opposed to the identity of) consciousness and plan execution. In section 2.10, he proposes that the operation of the plan-executing mechanism is necessary, but not sufficient, to elicit consciousness. As support for this proposal, he refers to the fact that unconscious planning and planned action occur in the context of routine and overlearned activities such as driving a car. Further support could be drawn from the neuropsychological literature. That planned action is not sufficient for consciousness seems clear enough.
1.5 Is planned action necessary for consciousness, as MIGHT be the case if plan execution were the cause of consciousness? Two lines of reasoning suggest a negative answer to this question. First, introspection would seem to indicate that it is possible to engage consciously in aimless free association. That is, phenomenologically, it does not seem to be the case that the "operations that make us conscious occur [only] in the context of controlling behavior from a plan" (section 2.9), even when behavior is broadly construed to include a mere play of ideas.
1.6 The second line of reasoning depends upon an appreciation of the distinction between conscious planning and the execution of a plan. Bridgeman acknowledges the significance of the distinction when he suggests that executing a routine plan may not meet various criteria for the recruitment of "deliberate attentional resources," which include (among other criteria) "planning or decision-making" (section 2.10). Elsewhere, however, he blurs the distinction, by repeatedly using the two terms interchangeably. Furthermore, any potential difference between the two types of phenomenon with respect to consciousness is precluded when Bridgeman writes, "An action plan becomes conscious only in the process of its execution" (section 3.10) and, "We become aware only of the plan currently being executed" (section 4.6). A growing corpus of data on executive functions-- the functions that make possible the execution of plans-- indicates that having a conscious plan does not entail being able to execute it.
1.7 Failures of executive functioning occur in normal adults and in patients with neurological damage (especially damage to the prefrontal cortex). However, they are characteristic of various points in ontogeny (see Dempster, 1992, for a review). Research in our laboratory suggests that there are considerable changes between the ages of about 2 and 5 years of age in the ability to use consciously accessible information to control behavior. Zelazo and Spinazolla (1992) conducted a series of experiments to determine whether 24-month-olds' perseveration in A-not-B search tasks (in which children retrieve an object at one location and then must search for the object when it is conspicuously hidden at a new location) is due to difficulty representing the object at a new location (a type of representational inflexibility) or to difficulty using an explicit representation of the object to inhibit a response to the old location and guide a response to the new location. We found that when children were merely shown the object at the old location without being allowed to retrieve it, they did not perseverate when the location of the object was shifted. However, when children were encouraged to make a response to the pre-shift location but were never shown the object at that location they perseverated repeatedly (as many as 32 times) on post-shift trials. The results indicate that on the post-shift trials j-- when the object was conspicuously hidden at a new location -- children knew where the object was but could not use that knowledge to govern their response. Research in different experimental paradigms has yielded analogous evidence of failures of response control at different ages. In some cases, children can state their plans verbally months or years before they become able to execute them (e.g., Zelazo & Reznick, 1991; Zelazo & Spinazolla, 1992).
1.8 There is clearly a relation between consciousness and intentional (or planned) action. Many of our plans are conscious; the execution of those plans often requires conscious activity (such as the conscious inhibition of prepotent responses or prepotent plans), and much of our conscious activity is involved in the goal-directed control of action. In so far as he attempts to explain the phylogenetic evolution of consciousness, Bridgeman seems to be looking in the right place; an account of the evolution of consciousness that emphasizes its connection to behavioral consequences (even if consciousness is a consequence of the creation of those consequences) would seem to be a fruitful way to approach the issue. The assimilation of communication to planned behavior more generally would also seem to be promising. However, there are a number of reasons to believe that the connections that lie at the crux of Bridgeman's account are less straightforward than he maintains.
Bridgeman, B. (1992). On the evolution of consciousness and language. PSYCOLOQUY 3(15) consciousness.1.
Dempster, F. (1992). The rise and fall of the inhibitory mechanism: Toward a unified theory of cognitive development and aging. Developmental Review 12: 45-72.
James, W. (1950). The principles of psychology, vol. 1. New York: Dover. (Originally published in 1890).
Zelazo, P.D., Palfai, T., & Frye, D. (1992). Embedded-rule use in sorting, causality, and theory of mind. Infant Behavior and Development (Special ICIS Issue) 15: 784.
Zelazo, P.D., & Reznick, J.S. (1991). Age-related asynchrony of knowledge and action. Child Development 62: 719-735.
Zelazo, P.D., & Spinazolla, J.F. (1992). Representational flexibility and response control in a search task. Infant Behavior and Development (Special ICIS Issue) 15: 785.