The cerebral cortex of the cat contains between 1 and 2 dozen representations of the visual field with different functional specializations. Six visual field maps lie along both banks of the suprasylvian sulcus, lateral and anterior to the visual areas in the occipital cortex. We have studied single-unit receptive field properties and their global organization across the visual field in 2 of these lateral suprasylvian areas, PMLS (essentially the Clare-Bishop area) and PLLS. Most neurons in PMLS and PLLS display selectivity for the direction of a light stimulus moving across their receptive fields with various degrees of directional tuning. We have used light spots of different size and velocity projected on a tangent screen in order to determine the direction preference of cells in these 2 areas. A strong tendency was found for neurons to respond best to centrifugal directions, i.e., to movement away from the area centralis. Thus, for these cells direction preference depends on the location of their receptive fields within the visual field. Velocity preference and binocular interaction in these neurons is also globally organized: Velocity preference increases with eccentricity, binocular synergism is strongest in the center of the visual field. Cluster analysis of recording tracks with respect to "radial" and "circular" cell categories reveals a grouping of cells with like properties in the lateral suprasylvian cortex. These new categories are formed by combining "centrifugal" and "centripetal" cells on the one hand and cells with direction preferences orthogonal to these on the other. The radial or centrifugal organization of direction preferences in conjunction with the global arrangement of velocity preference and binocular interaction suggests that PMLS and PLLS are involved in the processing of expanding visual flow fields of motion. Such flow fields are commonly encountered when a visual object moves towards an observer or during forward locomotion.

We have studied the orderliness of representation of visual space in the medial and lateral banks of the middle suprasylvian sulcus. Penetrations were made either parallel to the sulcus, in one bank or the other, or vertical, thus crossing the sulcus between the postero-medial (PMLS) and posterolateral (PLLS) divisions of this area. In some cases we found clear evidence for topographical order in the representation of the visual field with a tendency (greater in PMLS than in PLLS) for the receptive fields of cells recorded deeper in the walls of the sulcus to lie closer to the area centralis, but along many penetrations the receptive fields were so large and so scattered that no retinotopic arrangement could be discerned. In PMLS the receptive fields of the majority of units we studied were centered below and close to the horizontal meridian, whereas in PLLS they were distributed over both the upper and lower visual fields with an over-representation of the upper field. Receptive fields were significantly larger in PLLS (mean field area = 442.2 deg2) than in PMLS (mean area = 154.4 deg2); there was also less clear correlation between receptive field size and eccentricity in PLLS (correlation coefficient = +0.25) than in PMLS (corr. coeff. = +0.72). Analysis of the distance between the receptive field centres of consecutively recorded units demonstrated that the mean scatter in both PMLS and PLLS amounts to about half the average receptive field diameter. In summary the topographical representation of visual space is less orderly in PLLS, and may involve a wider area of the visual field. These findings may relate to the segregated visual cortical and extrageniculate thalamic connections that the medial and lateral banks of the LS receive.

Based on 36 interviews with women correctional officers, we examined their everyday work experiences in the Ontario Provincial correctional system. We used the Psycho-Social Ethnography of the Commonplace methodology to determine challenges and complications women endure in this highly gendered, masculine-defined culture, and the resilience approaches they used to survive. Findings indicate how sexism, hostility, paternalism, and social alienation are maintained and reinforced. Women are repetitively, implicitly and explicitly reminded of their fragile femininity, physical inferiority, and lack of fit. Policy recommendations to contravene the Culture of Corrections’ androcentric nature, and those found in other nontraditional men-dominated work environments, are offered.

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Areas PMLS and PLLS of the cat's lateral suprasylvian visual cortex display an interesting global organization of local features in their single unit response properties: direction preference is centrifugally organized and velocity preference increases with eccentricity. In addition it has previously been shown that binocular interactions are strongest around the visual field center. This characterizes the LS areas as apt for the analysis of optic flow fields and for visual processing in various kinds of visuomotor tasks (Rauschecker et al. 1987). In the present study we analysed the types of input to LS from the optic chiasm, the corpus callosum and from two thalamic relay nuclei (lateral posterior and lateral geniculate) that constitute important sources of afferent information to the LS areas. We were interested in learning how the afferent (and efferent) connections between LS and these structures relate to the response properties of LS neurons. Overlap of an RF into the ipsilateral hemifield was virtually always associated with callosal input. Latency differences between responses to electrical stimulation of the optic chiasm and the thalamic sites indicated almost exclusively fast-conducting Y-input to LS. Correlation of response latencies with receptive field properties revealed the following correspondences: A positive correlation was found between LP-latency and RF-size matching the dependence of RF size on laminar origin. The type of correlation found between LP-latency and directional tuning of LS cells suggests that an interaction between thalamic and other inputs may be responsible for direction selectivity in LS. Finally, correlation of LP-latencies with centrifugal direction preference suggests that this specific property is generated by intracortical wiring rather than by thalamic input.