Time-to-Collision (TTC) judgements with offsize objects show that Tau needs to be intergrated with familiar size to explain TTC performance

Observers judged TTC with computer-generated displays simulating an approaching object in three familiar-size conditions:

(i) Real-size (smaller, larger objects depicted as tennis, soccer balls respectively).
(ii) Off-size (smaller, larger objects depicted as soccer, tennis balls respectively).
(iii) Ambiguous-size (smaller, larger objects depicted as texture-less black balls of different size).

Displays simulated objects approaching observersí viewpoint from 24.96 m, and disappearing at 5.76 m. Manipulation of approach velocities (4.8-19.2 msec-1) produced viewing times from 1.0 to 4.0 sec, and delays between object disappearance and tau-based TTC ranging from 0.3 to 1.2 sec. Motion characteristics of smaller and larger objects in the three familiar-size conditions simulated those of approaching real-sized tennis and soccer balls respectively; that is, for each approach velocity, tau‚-based TTC was the same across the three conditions for smaller and larger objects.

Results showed that, consistent with the proposition of tau-determined TTC, TTC estimates in the real-size condition were uninfluenced by object size. This is contrary to previous reports that TTC for larger objects is underestimated relative to TTC for smaller objects. However, such size-dependent TTC differences were found in the ambiguous-size condition, with even larger differences in the off-size condition; TTCs for the ëlargerí tennis ball were much less than TTCs to the ësmallerí soccer ball compared to corresponding TTCs in the ambiguous-size condition. These results are problematic for the proposition that tau solely determines TTC. We discuss the role of perceptual learning in resolving this problem.

Potential of technology and a familiar context to enhance students' concept of rate of change

Students' concept image of rate of change may be incomplete or erroneous. This paper reports a pilot study, with secondary school students, which explores the potential of technology (JavaMathWorlds), depicting a familiar context of motion, to develop students' existing schema of informal understandings of rate of change to more formal mathematical representations. Students developed numerous 'models of' rate of change in a motion context which then transferred to serve as a 'model for' rate of change in other contexts.

Retrieval-induced forgetting of performed and observed bizarre and familiar actions

To investigate whether people show retrieval-induced forgetting (RIF) for bizarre and familiar actions that they performed or observed, three experiments were conducted. In Experiment 1, participants performed bizarre and familiar actions with different objects during learning (e.g., pencil: balance the pencil across the cup, sharpen the pencil). They repeatedly performed a set of the bizarre or familiar actions during retrieval practice. After a distracter task, participants’ cued recall was tested. Participants showed RIF for both bizarre and familiar actions. In Experiment 2, half of the participants performed the bizarre and familiar actions themselves; the other half observed the experimenter performing the actions. Replicating the results of Experiment 1, participants who performed the actions showed RIF for bizarre and familiar actions. In contrast, participants who observed the actions did not show RIF for either action type. Experiment 3 examined whether this lack of RIF for observed actions occurred due to a lack of active recall during retrieval practice; it did. Overall, the three experiments demonstrated RIF for both bizarre and familiar performed and observed actions. A distinctiveness account of the results is provided.

The strange and the familiar : seeing beyond when we know

My novel is a collection of interrelated stories. Each story is framed by the idiosyncrasies and prejudices of a different first-person voice. There are gaps in narrative time and there is disparity between the narrators’ voices. The result is a ‘discontinuous narrative’; this term describes the early work of Frank Moorhouse: ‘an innovative narrative method using interconnected stories’ (Griffith University 2011).
As I draft and re-draft the stories, I am forced to assess the interaction between the voices. I am aware of the disjuncture, and I ask myself: Why not tell the story through the eyes of one narrator? Why not choose a third-person perspective, an omniscient narrator who might collect all of the voices together, in a coherent way?
As I second-guess my approach, I realise that the splintering of voices feels like the right way to tell the story and, in this way, I approach the question of methodology. I am aware that a sense of disjuncture arises out of the medley of voices, but I also realise that the disjuncture is carefully constructed; it is not accidental. This is an intuitive judgement.
If I edit my novel ethically, I ask what the discontinuity achieves, rather than how it fails in the context of logic. This means that I recognise that the narrative begins from a place that does not worry about logic, and I realise that second-guessing the surface content of the narrative, from a rational perspective, may be counterproductive.
The conscious mind, fettered as it is with inhibitions, may fail to see that the logical track is not necessarily the most productive route. The conscious mind may not recognise that going off-track is the way forward and, perhaps, the only way that the story can become something other than what I, in my rational mind, believe that it should be.
Ethical editing means that I am attentive to my intuitive response to the narrative; it means that I tolerate incongruous elements of the narrative, even if they do not fit the criteria of logic.
Ethical editing is a meeting of minds (both mine); the fully conscious mind meets the work of the subconscious mind with surprise and approval, at best, skepticism and derision, at worst. The work of the subconscious mind is elusive but it need not be subjugated to logical, rational considerations, for this means that I delimit the work of the subconscious; it means I assess the discontinuity on the basis of an external operating system; it means that I impose certain criteria upon the surface narrative, criteria that has nothing to do with understanding why the discontinuity exists in the first instance.
Alternatively, when I pay heed to a primal moment of narrative composition, a moment that is not necessarily consciously determined or logical, I apprise the surface of the narrative as a metaphorical map, I attempt to engage with the possibilities for meaning that the map encompasses; this constitutes a quest for the unstable how of meaning attribution.