Abstract: A mass communication assessment system (2) communicating a cognitive task to selected remote test sites (12) via a network (10) for providing a two-way communication between the central control site and the remote sites, detecting brain response signals from the subject (40) to the task, and having processing means (16) for computing variations in the brain activity for the subjects at each of the selected sites.

Abstract: The invention relates to a method and apparatus of forming pellets and in particular spherical binderless pellets from lower rank coals. The method includes the steps of feeding a pelletizing means 10, with a lower rank feedstock, 1; rotating the coal in said pelletizing means, 10, to form pellets in the absence of any binder, wherein the pellets are formed by compaction and layering of coal fines. The moisture content of the lower rank coal is at a level so as to at least substantially fill the voids within the coal.

Abstract: Electrical activity of the brain is analysed by the application of a repetitive stimulus so as to evoke a steady state response, changes or differences in the steady state response being used as a measure of said electrical activity. The spatial distribution of the activity can be displayed as a topographical representation of the brain, which representation can be updated so as to provide a substantially real-time display. A neuro-psychiatric workstation incorporating such a display can be used for instance for various research purposes.

Abstract: Apparatus for controlling liquid from a site comprising at least three liquid retention cells which are arranged in series with respect to the flow path of the liquid through the apparatus, the liquid retention cells being arranged in at least one group which comprises at least three of said cells disposed adjacent one another, an inlet for delivering liquid to an upstream cell of the apparatus and an outlet for discharging liquid from a downstream cell of the apparatus to a discharge line, and transfer orifices which provide liquid communication between adjacent cells in the group, the or each transfer orifice being configured so as to control the liquid flow between adjacent cells and create a condition whereby there is a dissipation of energy of the liquid between each cell apparatus.

Abstract: A method and apparatus for determining the level of attention of a subject to a visual stimulus such as a television commercial displayed on a screen (4) so as to provide objective information for designing the advertising presentation. The technique involves reflecting visible red radiation from arrays (16) of LEDs towards the eyes of the subjects (2) as a control signal at a predetermined frequency. The control signal is first applied to the subjects and EEG responses obtained. The control signal is then simultaneously applied with the display of the television commercial and EEG signals are again obtained. An assessment of the subjects interest is then made by determining the diminution in value of the components of the EEG response attributable to the control signal. A pair of illuminated goggles is also disclosed.