fNIRS can robustly measure brain activity during memory encoding and retrieval in healthy subjects.

Early intervention in Alzheimer's Disease (AD) requires novel biomarkers that can capture changes in brain activity at an early stage. Current AD biomarkers are expensive and/or invasive and therefore unsuitable for use as screening tools, but a non-invasive, inexpensive, easily accessible screening method could be useful in both clinical and research settings. Prior studies suggest that especially paired-associate learning tasks may be useful in detecting the earliest memory impairment in AD.

Motor cortex is required for learning but not for executing a motor skill.

Motor cortex is widely believed to underlie the acquisition and execution of motor skills, but its contributions to these processes are not fully understood. One reason is that studies on motor skills often conflate motor cortex's established role in dexterous control with roles in learning and producing task-specific motor sequences. To dissociate these aspects, we developed a motor task for rats that trains spatiotemporally precise movement patterns without requirements for dexterity.

Finding motifs in birdsong data in the presence of acoustic noise and temporal jitter.

Here we present a novel approach to quickly and reliably find long (200 ms - 2 s) stereotyped sequences of sounds ("motifs") in acoustic recordings of birdsong. Robust and time-efficient identification of such sequences is a crucial first step in many studies ranging from development to neuronal basis of motor behavior. Accurately identifying motifs is usually hindered by the presence of animal-intrinsic variability in execution and tempo, and by extrinsic acoustic noise (e.

The basal ganglia is necessary for learning spectral, but not temporal, features of birdsong.

Executing a motor skill requires the brain to control which muscles to activate at what times. How these aspects of control-motor implementation and timing-are acquired, and whether the learning processes underlying them differ, is not well understood. To address this, we used a reinforcement learning paradigm to independently manipulate both spectral and temporal features of birdsong, a complex learned motor sequence, while recording and perturbing activity in underlying circuits.

Precision and diversity in an odor map on the olfactory bulb.

We explored the map of odor space created by glomeruli on the olfactory bulb of both rat and mouse. Identified glomeruli could be matched across animals by their response profile to hundreds of odors. Their layout in different individuals varied by only approximately 1 glomerular spacing, corresponding to a precision of 1 part in 1,000.

Rat olfactory bulb mitral cells receive sparse glomerular inputs.

Center-surround receptive fields are a fundamental unit of brain organization. It has been proposed that olfactory bulb mitral cells exhibit this functional circuitry, with excitation from one glomerulus and inhibition from a broad field of glomeruli within reach of the lateral dendrites. We investigated this hypothesis using a combination of in vivo intrinsic imaging, single-unit recording, and a large panel of odors.