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Rapid and accurate identification of emotionally meaningful stimuli has important benefits related to survival. In the current thesis, speeded detection of emotionally meaningful signals, including emotional facial expressions and emotional body postures, was investigated using two main experimental techniques; forced choice discrimination and exogenous cueing. To provide a direct measure of attention, and to further elucidate the time-course of emotional bias, the response mode of interest (manual or saccadic) and presentation duration of the stimuli (Short: 20ms) or (Long: 100ms; 500ms) was varied systematically across the experiments. Overall a consistent pattern of results was found where saccadic responses showed emotional bias at short, but not long stimulus durations, whereas manual responses evidenced emotional bias only at long stimulus durations. Besides from being detected more rapidly, evidence also shows that emotional stimuli are more likely than neutral stimuli to enter awareness. To further investigate this theory, the final series of experiments in this thesis employed a binocular rivalry paradigm. It was found that emotional facial expressions were associated with longer periods of dominance (i.e. they were perceived for longer durations) than neutral facial expressions. Taken together, the experiments reported in this thesis showed that attention is biased towards emotion conveyed not only by the face, but also by the body. Notably, both emotional facial expressions and body postures were detected more quickly than their neutral counterparts using saccades and manual responses and further, emotional facial expressions were more likely to be perceived in a binocular rivalry situation.

<i>PAX77⁺</i> mice were shown to express about 150% of wild-type Pax6 levels of corneal epithelial Pax6 and displayed abnormally small corneas due to a failure of postnatal growth and development of the cornea.  The proliferative component of the corneal epithelium was normal, cell cycle progression appears unaffected and there are no abnormal apoptotic events.  Cytokeratin-12 expression was down regulated in the <i>PAX77⁺</i>corneal epithelia, implying differentiation is incomplete, and the corneas of <i>PAX77⁺</i> were found to display increased fragility in comparison to wild-types. <i>PAX77⁺</i> corneas displayed sever wound healing abnormalities which in contrast to Pax6^+/-can not be rescued by EGF addition.  Both <i>Pax6^+/-</i> and <i>PAX77⁺ </i>corneal epithelia show no improvement in wound healing with addition of Shh peptide or all-trans retinoic acid (in contrast to wild-type), however in the <i>PAX77⁺ </i>wound healing abnormalities do not lead to corneal opacity which is seen in <i>Pax6^+/-</i>.  Both <i>Pax6^+/-</i> and <i>PAX77⁺</i>corneal epithelia have increased basal levels of retinoic acid signalling in their corneal epithelium when compared to wild-type littermates.  Topical application of Shh increased RA signalling in the corneal epithelium. As described above a severe reduction in corneal size was observed in the <i>PAX77⁺</i> mouse: defective lens signalling as a result of Pax6 dosage was postulated to lead to this.  The lens is highly sensitive to Pax6 dosage.  Mouse/chick secondary chimeras were produced, through the grafting of <i>PAX77⁺</i> and wild-type mouse lenses into a chicken eye, to investigate the role of altered Pax6 dosage in the lens on anterior eye development.  <i>PAX77⁺</i> mouse/chick secondary chimeras, remarkably recapitulated the anterior eye phenotype seen in <i>PAX77⁺</i> mice. This supports the role of altered Pax6 dosage in the lens resulting in the corneal abnormalities of the <i>PAX77⁺</i> model.