Performance reviews are the HR ritual that everyone dreads.

Brain science shows that positive or negative, the way in which that review gets delivered can be a boon or a curse. If a boss gives even a good review in the wrong way, that message can create a neural downer.

The neuroscientist Richard Davidson at the University of Wisconsin has found that when we're upbeat, our brains turn up the activity in an area on the left side, just behind the forehead. That's the brain state where we are at our best.

But when we're feeling down, even anxious, our brain has turned up the volume on the right side. That's the zone where we punt.

Performance feedback that focuses on what's wrong with us also puts this downer brain area on overdrive. We're so preoccupied with the bad news (and our fantasies of this meaning we'll lose our job) that we just don't have the energy or can't focus on working at our best.

Even the boss's tone of voice can trigger one or another brain area. In one study, when people got positive performance feedback that was delivered in a negative, cold tone of voice, they came out of the session feeling down - despite the good news.

Amazingly, when negative feedback came in a warm, positive tone of voice, they felt upbeat and energized.

Of course a boss needs to give employees performance feedback. But too many are poor at giving feedback. The problem here takes two forms: being hyper-critical and focusing only on what's wrong without balancing it with what's right, or undermining even positive feedback with a negative tone.

Either way, the messages the boss sends activate the wrong brain zone. Inept manager feedback makes us inept.

The bad news: this is rampant. The really bad news: it hurts business. That's the verdict of Samuel A. Culbert, a psychologist at the Anderson School of Management at UCLA. He says annual reviews do more than create more stress for workers. They end up making everybody - those who get them and those who give them - less productive.

In theory, artful performance feedback improves our performance, setting us on the right track. Such feedback is best given on the spot (not months later in a formal review), and with a sense of trust and openness between the giver and receiver. It might take the general form of "When you do X, it does not help get to Y, because of Z." The X and Z here should be a clear and specific - that is, actionable information.

But what happens when such on-the-spot feedback comes in the heat of the moment, when the manager is steamed and not caring the least about imparting X, Y, or Z? Managers have their emotional hijacks, too.

Then there's the nightmare of the formal performance review. Culbert argues they are largely a sham - a charade carried out to justify decisions on promotion or pay. And even when they do reflect actual performance, the feedback tends to be hollow rather than giving you a healthy balance of what you do well with what need to improve on - and how. So Culbert suggests instead a performance preview, where a boss outlines how an employee can do even better.

But the neuroscience adds a crucial nuance: even positive news should come with a positive tone. So add to that feedback a dollop of emotional intelligence.

Learn how to enhance your application of emotional intelligence with my book The Brain and Emotional Intelligence: New Insights from More Than Sound.

You may also consider taking part in Six Seconds' eWeek: Engage the Power of Emotions, a week-long online emotional intelligence series that includes free workshops and resources for managers, coaches and trainers.