Anthony J. Marcel

One process, not two, in reading aloud: Lexical analogies do the work of non-lexical rules.

It is widely held that there are two (non-semantic) processes by which oral reading may be achieved: (a) by known words visually addressing lexical storage of their complete orthography and phonology; (b) by parsing a letter string into graphemes which are translated by rule into phonemes. Irregular words (HAVE) rely on the former, new and non-words rely on the latter. Recent evidence casts doubt on this view; to meet some of this data a revised version is presented. An alternative view is that the phonology of both words and non-words, at each encounter, is retrieved by analogy with all known words having matching segments. In a mixed list of words and non-words, presented singly for pronunciation, phonologically ambiguous non-words (NOUCH) were preceded critically by words with the same ambiguous segments, either pronounced regularly (COUCH) or irregularly (TOUCH). Standard (and revised) dual-process theory predicts that preceding words will not affect pronunciation of non-words; analogy theory predicts that they will. Significant biasing effects, compared to control conditions, support analogy theory, but a further modification to dual-process theory enables it to deal with these results. However the presence in critical non-words of morphemes pronounced consistently or inconsistently with the biased pronunciations significantly affected biasing. This makes the case for lexical analogy theory even stronger. Formal knowledge (descriptive spelling-sound rules) may be used consciously, but does not reflect tacit processes in oral reading, which are better described by a single-process lexical analogy model.

TMS over right posterior parietal cortex induces neglect in a scene-based frame of reference

Although damage to right posterior parietal cortex (RPPC) produces bias in line bisection, Karnath et al. [Karnath, H.-O., Berger, M. F., Küker, W., & Rorden, C. (2004). The anatomy of spatial neglect based on voxelwise statistical analysis: A study of 140 patients. Cerebral Cortex, 14, 1164-1172] claim that it plays little role in spatial neglect, which is better measured by target cancellation. We used a detection task (approximating cancellation in requiring detection) to investigate this claim by compromising the parietal cortex with transcranial magnetic stimulation (TMS). Two outline shapes, one on each side of fixation, were briefly displayed before a mask. The target was a discontinuity in the left or right of the outline of one of these perceptual objects. Subjects indicated position or absence of target as fast as possible. Stimulus-mask onset asynchrony was adjusted individually to yield 75% detection. TMS was delivered over left posterior parietal cortex (LPPC), RPPC and Vertex, with Sham TMS over RPPC as a baseline control. Target detection was near ceiling and fastest at central positions and worst and slowest at the far right. Detection was significantly reduced at the far left position by TMS over RPPC. No other effects were obtained and latency was not affected by TMS. Disruption of RPPC by TMS does produce left neglect as measured by detection. Given the pattern of performance and since it was disrupted on one side of the display rather than on one side of each shape, attention and neglect were in a scene-based rather than object-based reference frame.

Negative set effects in character classification: a response-retrieval view of reaction time.

In most current accounts of character classification, emphasis is laid on the role of the positive set. Reanalysis of a previous experiment (Marcel, 1970) showed that in the constant set procedure, as well as the varied set procedure, when consecutive sets of digits are used, latency to negative probes depends on remoteness from the positive set boundary, except when the positive set consists of only one item. Two further experiments showed that in both the constant-and varied-set procedures, latency to individual negative probes decreased with their frequency, except with positive sets of one item. These data indicate that negatives are not usually classified as such merely by default. Some alternative models to Sternbergs are discussed. It is proposed that when he is able to (always with one-item positive sets) the subject will perform a physical match. Otherwise the probe will access its location in long-term memory, associated with which is appropriate response information. The ease of recovery of that information is emphasized as responsible for variation in latencies.

How many selves in emotion experience? Reply to Dalgleish and Power (2004)

T. Dalgleish and M. J. Power (see record 2004-15929-012) suggest that J. A. Lambie and A. J. Marcels (2002) article implicitly presents a unitary view of self in emotion experience and propose that certain clinical phenomena require multiple selves. This reply summarizes Lambie and Marcels usages of the term self and examines both Dalgleish and Powers gloss of these and their own usages. This indicates that their own central usage of the term misrepresents Lambie and Marcel and is itself an improper usage. More important, examination of the phenomena claimed to require multiple selves suggests that they do not and that Dalgleish and Power may have misread the relevant clinical literature. Finally, Lambie and Marcels own conception of dissociative phenomena and multiple selves are outlined, and alternative approaches are sketched. In discussing the usages of the term self and interpretation of cognitive and affective disorders, this reply attempts to clarify certain confusions.

Structured perceptual input imposes an egocentric frame of reference - pointing, imagery and spatial self-consciousness

Perceptual input imposes and maintains an egocentric frame of reference, which enables orientation. When blindfolded, people tended to mistake the assumed intrinsic axes of symmetry of their immediate environment (a room) for their own egocentric relation to features of the room. When asked to point to the door and window, known to be at mid-points of facing (or adjacent) walls, they pointed with their arms at 180° (or 90°) angles, irrespective of where they thought they were in the room. People did the same when requested to imagine the situation. They justified their responses (inappropriately) by logical necessity or a structural description of the room rather than (appropriately) by relative location of themselves and the reference points. In eight experiments, we explored the effect on this in perception and imagery of: perceptual input (without perceptibility of the target reference points); imaging oneself versus another person; aids to explicit spatial self-consciousness; order of questions about self-location; and the relation of targets to the axes of symmetry of the room. The results indicate that, if one is deprived of structured perceptual input, as well as losing ones bearings, (a) one is likely to lose ones egocentric frame of reference itself, and (b) instead of pointing to reference points, one demonstrates their structural relation by adopting the intrinsic axes of the environment as ones own. This is prevented by providing noninformative perceptual input or by inducing subjects to imagine themselves from the outside, which makes explicit the fact of their being located relative to the world. The role of perceptual contact with a structured world is discussed in relation to sensory deprivation and imagery, appeal is made to Gibsons theory of joint egoreception and exteroception, and the data are related to recent theories of spatial memory and navigation.

What does it mean to ask whether cognitive skills are prerequisite for learning to read and write?—A response to cossu and marshall

Abstract In this issue of Cognitive Neuropsychology (pp. 21–40) Cossu and Marshall report the case of a 9-year-old Italian child (TA) who (like other “hyperlexics”) has learned to transcode print to sound and vice versa, to a certain level of competence, and yet appears to lack several other abilities which various theorists have implicated in learning to read alphabetic script. The authors infer that these other abilities are not prerequisites for, nor even implicated in, learning to transcode in either direction, and that this is the strongest evidence for the “modularity of transcoding skill”. While the data add little to the literature on hyperlexia, it is most useful to examine the implications of confronting different research literatures which rarely make contact. However, the status, treatment, and theoretical interpretation of the data in Cossu and Marshalls paper are worrying. They raise issues that go beyond this individual publication. Among such issues are the following: 1. The nature of a d...

On a neurofunctional theory of visual consciousness: commentary on J. Prinz.

Prinzs theory of visual consciousness has two main components. First, the content of visual consciousness is equal to Marrs intermediate level or 21/2 D sketch, and its neural site is the parts of the visual system that encode such content. Second, what one is visually conscious of depends on attention, and automatic nonconscious higher-level processing of the input is fed back to the intermediate level to confirm or complete what is selected or to alter attentional mechanisms. What is conscious is only what is attended. I hope that this extreme precis is fair. I might expect to be sympathetic to this scheme, because with some important exceptions the second part is very similar to what I proposed in 1983. Indeed I am sympathetic to much of the paper. However, (a) the view that perceptual consciousness is always and only at one level of description is problematic, and (b) the proposal has other problems both conceptual and empirical.