![Sample our Humanities journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/5939/TOC-Subject-Sample-2021-Humanities.jpg"})
Abstract
In this paper I aim to present an explanation of object permanence that is derived from an ecological account of perceptually based action. In understanding why children below a certain age do not search for occluded objects, one must first understand the process by which these children perform certain intentional actions on non-occluded items; and to do this one must understand the role affordances play in eliciting retrieval behaviour. My affordance-based explanation is contrasted with Shinskey and Munakata's graded representation account; and although I do not reject totally the role representations play in initiating intentional action I nevertheless maintain that only by incorporating direct perception into an account of object permanence can a fuller understanding of this phenomenon be achieved.
Notes
1. Psychologists have been quick to dismiss, by way of explanation, any account that suggests that the infant's failure to search is due to either (1) a diminished interest in the hidden object, or (2) underdeveloped motor skills. To counter arguments (1) and (2) there is evidence that young infants show signs of distress when desired objects are occluded, and are quick to grasp them even when only partially uncovered (see Baillargeon Citation1986; Baillargeon et al. 1990).
2. Recent research, however, has revised this date in favour of an earlier onset—at around seven or eight months (see Baillargeon et al. 1990). Despite this slight amendment, the general findings of contemporary researchers have been in many other respects consistent with Piaget's early observations regarding the switch from inertia to action.
3. The idea is that the child's cognitive development passes through different stages of maturity each qualitatively different from the last. Such stages are dependent upon brain maturation and interaction with the environment. Each, in effect, signals a new qualitatively different way of understanding the world.
4. I say ‘consistently’ in recognition of the fact that on some occasions the child may fail to retrieve an occluded object simply because she has switched her attention to something else, or is happy for the object to remain hidden (etc.).
5. These findings also refute Bower's (1967) claim that failure to search is the result of poor memory rather than a lack of understanding about the existence of unperceived objects. According to Bower, children fail to search because they forget where the occluded object is. However, the work of Baillargeon (and others) fails to support such a conclusion as the memory capacity exhibited by infants in the violation of expectancy trials is greater than that needed to execute a successful retrieval response during the standard Piagetian test.
6. For a suitable research link, see Warren and Whang Citation(1987). In this study they examine the affordance of ‘enterability’ and note the constant relationship (ratio) that exists between aperture and bodily rotation when walking through doorways of ever decreasing width.
7. The term ‘appears’ used here is referring to a pre-reflective level of awareness—that is, a level of consciousness in which the content of the mental state is not itself the object of conscious reflection.
8. Mark Citation(1987) defines affordances in a similar way, as ‘the functional utility of certain environmental objects or object complexes taken with reference to individuals and their action compatibilities’.
9. For early research, see Trevarthen Citation(1968), Schneider Citation(1969) and Ungerleider and Mishkin Citation(1982). However, for a more up-to-date discussion on these diverse visual pathways and their function, including refinements and amendments, see Milner and Goodale Citation(1995), Norman Citation(2002) and Goodale and Milner Citation(2004).
10. Originally, the distinction between the two pathways was believed to be based on (ventral) recognition (‘what’ the object is) and (dorsal) location (‘where’ the object is). However, recent refinements in research has led to a re-think concerning the ‘where’ system. It is now believed to subserve the subject's ability to engage with the object, rather than simply its spatial location. Consequently, it is thought of more as a ‘how-to’ system and, as such, emphasis is now placed on the output—in the form of visuomotor responses—rather than the input of visual information (see Bertenthal Citation1996, 433; Goodale and Milner Citation1992).
11. As well as the cortical system (with its two latter projections from the occipital area V1), there is also a sub-cortical projection from the retina directly to the midbrain (the posterior parietal cortex—the same projective destination as the dorsal stream). The sub-cortical system that projects from the superior culliculus to the midbrain is also implicated in visuomotor action. Information processed along this pathway contributes to the skilled, visually guided motor-performance capabilities of the subject (like the dorsal stream). However, it will not be discussed further in this paper.
12. It is worth noting that this conscious/non-conscious distinction is not absolute. Some ventral stream processing is believed to occur at a non-conscious level and, conversely, some dorsal stream processing can be brought into conscious awareness. However, why this should be or what factors determine whether a process is conscious or non-conscious are, at present, unclear (see Goodale and Milner Citation2004, 113).
13. See, also, Milner and Goodale's Section 4.1 on spatial coding (1995, 88–92).
14. For additional support, see Bertenthal Citation(1996) and Hofsten et al. (1993, 1994).
15. See Milner and Goodale (Citation1995, 6 and 50).
16. An object may, of course, afford an action that is made up of a number of different actions. McGrenere and Ho (Citation2000, 2) use the example of ‘eating’ which is composed of a number of separate actions—biting, chewing, swallowing. These they term nested affordances: something they claim is implied by Gibson but not given a specific term.
17. By ‘weak’ or ‘strong’ affordances I am anticipating a possible line of argument in which the subject is said to perceive a number of potentials for action, some of which elicit a stronger response than others. Therefore, although many affordances are perceived, it is the strongest affordance that elicits action. I reject this position, for reasons discussed.
18. See Humphreys Citation(2001) for a brief overview.
19. CD suffers from a condition known as visual apraxia.
20. There is also anecdotal as well as empirical evidence to suggest that affordances can disrupt category selection in ‘normals’ as well as clinical subjects (see Humphreys and Forde 1998; Reason Citation1984; Rumiati and Humphreys Citation1998; for more details).
21. Again, see Humphreys and Forde (1998), Reason Citation(1984), Rumiati and Humphreys Citation(1998) and for more details.