Functional magnetic resonance imaging (fMRI) was used to estimate the average receptive field sizes of neurons in each of several striate and extrastriate visual areas of the human cerebral cortex. The boundaries of the visual areas were determined by retinotopic mapping procedures and were visualized on flattened representations of the occipital cortex. Estimates of receptive field size were derived from the temporal duration of the functional activation at each cortical location as a visual stimulus passed through the receptive fields represented at that location. Receptive fields are smallest in the primary visual cortex (V1). They are larger in V2, larger again in V3/VP and largest of all in areas V3A and V4. In all these areas, receptive fields increase in size with increasing stimulus eccentricity. The results are qualitatively in line with those obtained by others in macaque monkeys using neurophysiological methods.

The macaque V5/MT complex comprises several sub-regions but little is known of their human homologues. We examined human V5/MT with fMRI in terms of specificity to optic flow stimuli, a key characteristic of macaque MST. Stimuli were large fields of moving dots, forming coherent global flow patterns. Random motion was used as a control. Retinotopic mapping was also conducted. The previously suggested existence of at least two distinct sub-regions, MT and MST, within the V5/MT complex was confirmed. Human MT is activated about equally by all moving dot patterns, including random motion, suggesting that it has little sensitivity to global flow structure. As previously described, this region shows strong signs of retinotopic organization and is only weakly activated by stimuli confined to the ipsilateral hemifield. In human MST, located immediately anterior to MT and strongly driven by ipsilateral stimuli, activation varies markedly with optic flow structure. The strongest activation is produced by complex flow that contains multiple flow components (expansion, contraction and rotation). Single components produce rather less response, while rigid translation and random motion produce less still. The results suggest that human MST is strongly specialized for encoding global flow properties, while human MT is less so.

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The positive BOLD (blood oxygen level-dependent) response elicited in human visual cortex by a localized visual stimulus is accompanied by a reduction in the BOLD response in regions of the visual cortex that represent unstimulated locations in the visual field. We have suggested previously that this negative BOLD reflects attention-related suppression of neural activity, but it might also be explained in terms of "blood stealing," i.e., hemodynamic changes that have no neural correlate. We distinguish two possible hemodynamic effects of this type: (1). blood flow reduction caused by locally reduced pressure in vessels that share their blood supply with nearby dilated vessels; and (2). blood flow reduction caused by active constriction of vessels under neural control. The first is ruled out as an explanation of negative BOLD by showing that a visual stimulus that stimulates primary visual cortex in one hemisphere can cause extensive suppression in the other hemisphere i.e., it is not a local phenomenon. Negative BOLD most likely reflects suppression of neural activity, but could also reflect an active blood flow control system.

We sought to understand the patients' 'lived experiences of systemic lupus erythematosus (SLE)' by exploring, describing and clarifying the patients' perspective of how they felt about having SLE and how the disease impacted on their lives, both positively and/or negatively. An interpretative phenomenological approach was employed. Semi-structured interviews were undertaken with 30 females with SLE across a wide range of age (21 to 75 years), disease characteristics, disease duration (1 to 28 years) and ethnicity (Whites, South Asians). Eleven themes emerged as important to the patients: prognosis and course of disease; body image; effects of treatment; emotional difficulties; inability to plan due to disease unpredictability; fatigue; pain; career prospects and loss of income; memory loss/concentration; reliance on others to assist with everyday tasks; and pregnancy issues. Most patients reported a negative impact of SLE on their lives although a few patients found positive aspects to having SLE. The findings of this study identified themes important to patients with SLE and these themes will inform clinicians on the patients' perspective of having SLE.