VISUAL ART:TO DESCRIBE Stephen Brandes's work as eclectic is to understate the case. In Walpurgisnachtat the Rubicon Gallery, he shuffles through a bewildering panoply of styles, media and forms of presentation. The latter range from a huge new lino drawing - a format that seems to be his own invention - to small mixed-media paintings on stretched canvas, casual sketches on paper and collages, variously framed and unframed. All of which are installed in the gallery in an irregular patchwork rather than following a conventional linear pattern, as if to emphasise that we are not going to be allowed to settle into a single, consistent mode of representation, writes Aidan Dunne

Rather, we alternate between comic-book illustration, graphic design, schematic drawing, pictorial abstraction and other visual codes. For some time now, Brandes has used his own family history, a picaresque chronicle of European migration in which pure, outlandish chance outmanoeuvred conscious planning at every turn, as source material with which to explore ideas relating to place, identity, community, stories and story-telling. His works are in a sense travellers' tales that are both everyday and exotic, infused with a sense of magic and wonder, but also with a deadpan quality, as though the implied narrator has seen it all and is not going to be disconcerted by anything fate can conjure up.

Surely Brandes's stylistic promiscuity has to do with his implicit assertion that lives as lived are more various and strange than any one system of representation will allow. The large-scale drawing on lino, a sort of stylised, topographical map of part of England, is built from dense linear patterns in ink, a form of repetitious labour rather than spontaneous inventiveness and, like repetitious labour, it has a soothing, almost hypnotic effect, lulling us into a state of meditative consideration. A certain dreaminess also attends his paintings, though they are inventive and spontaneous, and very successfully so. It's well worth visiting Walpurgisnacht and letting it tell you its stories.

Finola Jones has a knack for putting together multi-faceted installations with the sure touch of a skilled stage designer, and there is something poised and theatrical about her show, The Work of Memory - From a Great Distance, at the Oonagh Young Gallery. The theatricality is admittedly enhanced by the aural element: a lush, beautiful aria from Bellini's opera La Sonnambula. This majestic score presides over an unlikely congruence of elements, including a projected view of a huge column of smoke or steam issuing from an industrial chimney in the midst of a chill river landscape and five cathode-ray television sets perched on little modernist tables. A decorative plate depicting ducks hangs on the wall to the side.

The television pictures counterpoint the projected landscape, depicting a moon, an off-air abstract pattern and three views of people sleeping, one of whom, we are told, is Carol, snoring loudly on Big Brother. It seems unlikely that all this can be encapsulated in terms of concise meaning or message, but it is dramatically engaging and, incidentally, makes one wonder how Jones would fare as production designer for an opera. There are reasonable interpretive possibilities. For example, the retrospective domesticity evoked by the arrangement of the televisions is an echo of an era that's been put to sleep, so to speak, its utopian promise succeeded by the post- modern larkiness of Big Brother. All those resources, meanwhile, all that energy has, the background image might imply, gone up in smoke.

Siblings John and Joy Gerrard do not work collaboratively as a team, but there is a logic to their pairing in Temple Bar Gallery's current show. John has built a significant international reputation on the basis of his technically remarkable works involving the still and moving photographic image. From the first he has taken to the digital age as though it's encoded in his DNA. He has consistently operated at that edge of things where evolving technical possibilities intersect with philosophical questions, in a way that most closely recalls Bill Viola's involvement with video recording technology.

With any new technology, there is an obvious risk that the novelty of its intrinsic properties will overshadow other considerations. Early on it did seem that John Gerrard was so enthralled with the image-making possibilities of digital media that he might drift into a form of CGI for its own sake, but that has not happened and he has used the technology to explore ideas relating to perception, reality and our experience of time. In Dust Storm(Manter Kansas 2007), he apparently orchestrates a dust storm in the setting of the wheat-producing plains of the American mid-west. The landscape is extraordinary looking in itself, so geometrically spare and well-defined that it resembles a scale model of the real thing.

The interactive dust storm has an ominous, threatening presence, and could be interpreted symbolically, not least because the work reportedly incorporates footage of a dust storm in Iraq recorded by an American soldier. In any case, the image of an archetypal American landscape menaced by a huge, capricious force carries considerable resonance in any of several ways. There is a real visual correspondence between John's Dust Stormand Joy's ambitious, large-scale drawing which features a huge, cloud-like mass of humanity.

In her work, Joy has shown consistent interest in the psychology of crowds and public, architectural spaces, concerns that inevitably bring to mind Elias Canetti's Crowds and Power, which examines mass political movements and the mob instinct. Joy's drawing, Protest Crowd 3, is a tour-de-force, easily one of the best things she's done.

Against an elegantly indicated architectural framework, a vast, milling crowds is barely contained, its energies pressing against the boundaries with a sense of potential violence, as though caught on the point of turning into a destructive mob. What's particularly good about it is that we have a glimpse of how things might go either way: the crowd might embody a legitimate cause, or it may be a vengeful, vindictive rabble. We are invited to dwell on the ambiguities and implications.

WalpurgisnachtNew works by Stephen Brandes, Rubicon Gallery, 10 St Stephen's Green, until May 31; The Work of Memory - From a Great Distance New work by Finola Jones, Oonagh Young Gallery, 1 James Joyce St, Liberty Corner, until May 31; Joy Gerrard/John Gerrard, Temple Bar Gallery, 5-9 Temple Bar, until May 31.