MIT Colloquium on Brain & Cognition with Mark Andermann, PhD

Selective processing of need-relevant cues: a dialogue between hypothalamus and cortex

We rarely gaze at a scene and itemize every object. More often, we search our surroundings to identify the objects we seek among the clutter. Pioneering electrophysiological studies of visual cortex in behaving primates demonstrated that the same group of neurons can extract different information from a scene depending on abstract prior instructions. Efforts to replicate these experiments in mice are multiplying. In many ways, however, mice are like children – they are slow to accept instructions, yet they readily attend to objects they crave. Indeed, while motivation is deliberately held fixed in most studies of selective attention, all mammals naturally shift their focus toward need-relevant sensory cues (e.g., visual cues associated with food) to meet the changing needs of the body (e.g. energy deficit). Our lab is exploiting these basic need states, and the genetically-defined hypothalamic neurons that control these states, as a natural means to direct a mouse’s attention toward need-relevant cues. As mice transition between satiety and hunger, we track neural responses in previously inaccessible regions of lateral association cortex during well-controlled visual discrimination tasks. Need states may enhance perception and learning by selectively boosting the responses of neurons in cortex and amygdala to need-relevant sensory cues. In turn, such responses to need-relevant cues may regulate the hypothalamic neurons controlling specific motivational drives. Establishing mechanistic links between historically disparate circuits governing homeostasis and cognition should help decipher how we flexibly attend to need-relevant sensory cues and associated outcomes.