Call it entertainment, call it distraction, call it sad. Or call our increasing amounts of screen-time inevitable: it's almost 60 years since commercial TV came to Australia, more than 20 years since the internet went public here, and a decade since YouTube was launched. We might think they are all competitors - pundits predicting the imminent death of broadcast TV - but here, with this boy getting his fix and his parents planning to augment theirs, we can see they are all on the same seductive spectrum.

We are addicted - but what are our screens really doing to us? And what drives us to them?

Amid statistics showing 92 per cent of Australians use the internet, we grapple with a dizzy array of offerings competing for our attention. There's video on demand, subscription, pay-per-view and catch-up TV, plus myriad internet-based content,  but the fact remains we are spending more time overall on screens big and small for information, entertainment, communicating with each other and for mere time-filling.

And, you might well argue, it is all doing exactly what traditional TV channels have always done - fighting for our precious viewing time. "TV", as we once knew it, has simply been re-packaged into all these evolving forms.

Whatever the case, it is all part of a natural progression. Once, we gathered around to watch the cave fire together. Then it was entertainment in the village square. Then the piano, the wireless, and eventually the flash new telly (launched in Melbourne just in time to watch the 1956 Olympics). Now, while younger people (18-24) spend more time on alternative devices (mobiles, laptops, tablets) than do older generations, they still spend the overwhelming majority of their total viewing hours each month in front of television sets, according to the Australian Communication and Media Authority.

TV hasn't died; it's evolved. And, anyway, our cravings are not about the technology, the devices per se: our screen time is all about what (content), when (delivery speed and  availability) and where (anywhere). We don't really care about how.

That's why one Wired magazine commentator's recent speculation is so attractive: imagine a single web-based entertainment service provider that could aggregate and store all movie and TV programs in the cloud and make them deliverable to all devices. One bill, almost endless choice, just like the internet - an internet that, Netflix executive Ted Sarandos said recently, has attuned us to get what we want when we want it.

Broadcast TV used to be called (like religion) the opiate of the masses but we have become greedy. We want our chosen content now, we binge on multiple episodes of Game of Thrones, Homeland or House of Cards, and we scoff at geo-zoning. We download illegally not because we are cheapskates but because we want our next fix, our next diversion, now.

At the National Gallery of Victoria, curator Maggie Finch has in recent months been excavating works of art from the collection that chart the rise of TV and question its lasting legacy. Finch notes how difficult it is to have one simple definition of TV because it operates differently across different regions, political zones and technological structures. But she likes a description by Australian artist Susan Fereday who said TV is a seductive medium because it "reduces everything to a kind of media-hum, a blue glow of interchangeable information and content". She might well be talking about the broader media landscape.

In the exhibition Transmission: Legacies of the Television Age, which Finch is curating, artists investigate screens, broadcasting, technology and transmission. Some celebrate what TV has given us, but many,  especially early video artists from the 1960s and '70s, critique it. Finch has been particularly interested in what artists have to say about TV news, with several works dealing with the Vietnam War, known as the "living room war", and how we viewed it. This untitled John Immig work comes from his Vietnam series, 1975-76.

Artists, perhaps, are the best people to show us what TV's effects have been, and how its latest evolution into multiple devices and myriad platforms delivering content is continuing the push for instant satisfaction. In Transmission, we also might reflect on our desire for screens to increasingly give us something resembling reality: just look at the metamorphosis of TV sets over the years from black-and-white TV to colour, from flat-screen plasma and LCDs to high-definition, and now the move to 3D and 4K units, with holograms no doubt on the horizon.

"We are in the middle of a fascinating, transitional moment," Finch says.

More and more, our screens mediate our experiences and our lives, but how do we feel about that? Melbourne artist Elvis Richardson is blunt. "We feel overwhelmed, generally overloaded in some way. That is why that whole counter-culture of the local, the analogue, has become such a strong presence, to help us get a grip on it."

Richardson was in Manhattan on a scholarship at Columbia University when the planes hit the twin towers in 2001. She had just dropped her son at day care and had rounded a corner when someone ran up and told her what was happening. She and some others went into an apartment, and they watched it unfold - not from a window but on the TV.

"I had people calling me from Australia who knew more about what was happening than I did," she says. Today, her memories of that terrible spectacle have all been filtered and compromised by TV footage such as this...

To understand and reflect on what she'd seen, Richardson made artworks about it, and one is showing in Transmission. For the stop-animation work, she interviewed people about where they were on September 11, and uses their words written on the screen blackboard-style. TV is frequently invoked in the interviewees' comments: "So I saw it live," says one, whose comments are captured in this image from Richardson's work. "I started plugging videos into the machine and recording everything I could," says another.

Fourteen years on, we might still gather around a TV set to gawk and gasp at such an event, but it would not only be filtered through a broadcaster such as CNN but through the Twitterverse and Facebook as well, viewed on all sorts of screens in all sorts of locations.

Do we hanker for the ritual associated with broadcast TV? ABC's Q&A is a highly successful hybrid, designed as a live weekly TV program in which viewers participate: it encouraged tweeting long before Twitter was well-known and now generates more than 30,000 tweets each episode, showing an average of 175 on screen each week. It's a date people love to keep because they feel a part of the stimulating conversations.

"Now those comments provide an extra layer to the discussion that's an integral part of Q&A," says the show's executive producer, Peter McEvoy.

Artist Eamon O'Toole​ is fascinated by these changes to our lives and his work in Transmission speaks of the days when televisions were pieces of interior design.

In the early days of TV, parents would worry that their children's eyes would go square or that they were soaking up harmful rays. Children would be told not to sit too close (addictive behaviours were evident even way back then). Curiously, these days - with parents and kids off on their own devices watching whatever they like - we might find ourselves nostalgic for the comparatively social event that was the TV dinner (and that has continued with something like Q&A). Broadcast TV offered ritual, a schedule and a ratings season that gave the screening experience some boundaries.

O'Toole recalls having a big old television always playing in his studio while he worked. It would be a background hum, a drone, until something, usually to do with motor sports,  would grab his attention. His favourite program was Wide World of Sports: the theme music was a cue that would draw him in every time. "It was like you'd been trained to suddenly pay attention and start watching," he says.

He made this sculpture, Wide World of Sport TV, 1988, which is like a crumpled television.

It's organic, solid and distinctly separate from our bodies. Screens have now moved increasingly closer to our bodies, their design more discreet and bland. They call attention to themselves not as objects but as portals to somewhere else.

What, though, lies under our urges to go through those portals? Perhaps it is the way a screen resembles our mind's eye - the inner canvas where we "see" our dreams and where our imaginations project images. But, unlike our imaginations, the imagery on our technology-based screens comes pre-packaged. We don't have to do any work, or create; we just forget our life's cares and let ourselves passively be carried away.

New York-based artist Dora Birnbaum​ was one of many people who was concerned in the 1960s and '70s about what TV was doing to us, a concern reflected in works such as Technology/Transformation: Wonder Woman.

Birnbaum wanted, says Finch, who interviewed her for Transmission, to halt the passivity she thought TV was bringing. "She felt that TV was really talking at her, that it was a one-sided conversation, that it was part of a strong power structure," Finch says. "The idea of breaking or disrupting that structure is at the heart of a lot of her work."

Layered across the top of such concerns is more recent scientific data about what screens do to us. Oxford University neuroscientist Baroness Susan Greenfield has written widely on how young brains are being reshaped by screen-based technology, especially the impact on imagination. She says electronic devices affect the micro-cellular structure and complex biochemistry of our brains, in turn affecting personality, behaviour and essential human identity.

New Scientist reported in November on several studies showing how our multi-screening, with its built-in distractions, is affecting our ability to read and write. Two pieces of research showed the difference in our ability to take in both factual and emotional data when reading an e-book or information on a laptop when compared with reading old-fashioned hard-copy on paper or in a book. The latter, unsurprisingly, was more effectual.

Scientific American reported recently, too, that being online all the time changes our subjective sense of self as borders between personal memories and information distributed across the internet start to blur. That's a worry when you look at ACMA research showing more than 70 per cent of teens go online more than once a day, most of them describing it as "very important" in their lives. As children become older, the research found, "going online becomes a central activity for social interaction, education, knowledge gathering and exposure to new experiences. It becomes an integral part of their lives."

What is in store for them? We might think of technology as, potentially, a convenient way to outsource our memories and intellectual data - just call up that information  when we need it - but what is left of us, then? What are we if not the sum of our memories, ideas and thoughts?

New York artist Ryan Trecartin takes up all such issues. Described effusively by one New Yorker critic as "the most consequential artist to have emerged since the 1980s", Trecartin and collaborator Lizzie Fitch examine pop, consumer and online cultures in  video works. One of these is an immersive theatrette resembling a teenager's lounge room, where visitors experience Trecartin films.

The works are a melange of reality TV, MTV, webcams and video-blogs all dealing with the concepts of identity and branding in an age where our screen experiences are incredibly intense. NGV curator Simon Maidment says Trecartin's movies are full of speed, neuroses, gossip, confessions, hysteria and exhibitionism, set within a complicated industry of "metaphysically evolved market research" where the commodity is personality traits. We are, it seems, becoming increasingly embedded in the screen world.

I reflect on all this as, back at the hi-fi store, I move past the silent, frowning toddler-with-tablet and inspect one of the giant internet TVs. They are glorious. A feeling of rainy-day self-indulgence overwhelms me. Where is the couch, the mohair blanket, the cup of tea? I want to lose myself.

As I become aware of these feelings, I notice that the TVs are roughly the size of many of the paintings we see in art galleries. And I wonder whether the unique stillness of art - engaging our inner eye of contemplation, entering an imaginative space - is in any way more fulfilling, more enriching, than the rush of images we devour on our screens. I wonder, like those 1960s artists intrigued by TV, what is happening to us.

Perhaps we'll only be sated when our screens are part of us, post-humanly grafted into our retinas, streaming straight to the cortex. Or perhaps we'll give it all up, or lose it in some unforseen technopocalypse. Stay tuned.

Transmission: Legacies of the Television Age and Ryan Trecartin: Re'Search Wait'S are both at NGV International May 15-September 13. ngv.vic.gov.au