Neurology

Dysfunction in a region remote from a lesion because of disrupted interactions with the damaged region. Reduced local activity after stroke can therefore reflect more than destruction of the locally measured tissue.

A syndrome of cognitive decline affecting everyday functioning, arising through different diseases. Age at reported symptom onset, age at diagnosis and the incidence of new cases are distinct outcomes.

A sudden neurological injury caused by disruption of cerebral blood supply or bleeding. Vascular anatomy can make damage to neighboring tissue and pathways covary, limiting attempts to infer one-to-one mappings from brain lesions to computations.

A neurodegenerative disorder with motor and nonmotor manifestations, including motivational difficulties in some patients. Comparisons across dopamine-related medication states can inform mechanisms but do not selectively manipulate a single cognitive process. The disease name commemorates James Parkinson.

Paralysis affecting one side of the body. Awareness of this impairment and ability to perform movement are distinct clinical questions.

Neurologist and researcher on language function after stroke.

Neurologist studying cognitive disorders and bilingual experience.

Neurologist studying language and primary progressive aphasia.

A neurologist whose work investigates reward, effort and apathy, including experimental choices in Parkinson's disease.

A neurologist whose case reports linked severe loss of spontaneous activity with bilateral basal ganglia injury and relative preservation under external stimulation.

A neurologist whose studies helped characterize semantic dementia as a progressive disorder of conceptual knowledge.

A neurologist whose report of associative visual agnosia examined visual recognition in relation to copying and other accompanying deficits.

A neurologist whose work on aphasia helped motivate anatomical and functional distinctions within language processing. Clinical syndromes bearing his name must still be explained through specific representations and computations.

The study of how neurological disease and injury affect cognition, using clinical patterns and experiments to constrain explanations of normal cognitive function. A brain lesion can disrupt connected regions and several computations, so a syndrome is evidence to explain rather than a complete processing model.

Reduced goal-directed activity or motivation relative to a person’s previous functioning. Initiation, valuation, effort and emotional experience require separate assessment; inactivity is not automatically anhedonia or motor incapacity.

A marked reduction of spontaneous initiative or willful activity. Preserved behavior after prompting can help distinguish impaired self-initiation from inability to execute the same action.

A severe reduction of spontaneous mental and behavioral activity that improves with external stimulation or instruction. Clinical descriptions after bilateral basal ganglia injury motivated experiments separating self-activation, incentive translation and motor capacity.^[ref]

A progressive syndrome with deterioration of conceptual knowledge, often accompanied by fluent speech, anomia and poor word comprehension. Nonverbal semantic tests are important for distinguishing broad conceptual impairment from an isolated language-output problem.^[ref]

Impaired recognition of visually presented objects not adequately explained by elementary visual loss or a general inability to respond. Testing other sensory routes and nonverbal knowledge helps locate the difficulty.

A visual-recognition disorder attributed to difficulty accessing meaning from a relatively adequate visual representation. Copying can provide evidence about perception, but line-by-line copying alone does not demonstrate normal integration.^[ref]

A visual-recognition disorder in which constructing or integrating an adequate perceptual representation is impaired. The specific perceptual demands must be established rather than inferred from recognition failure alone.

Impaired awareness of a neurological deficit. Its assessment must distinguish the underlying deficit, a person’s report and evidence that they understand the relevant questions.

Difficulty performing learned actions not adequately explained by elementary weakness, sensory loss or failure to understand the instruction. Different clinically named forms need not share one processing mechanism.

Difficulty organizing dressing actions that can involve relationships between clothing, the body and space. Motor limitations, understanding and neglect require separate assessment.

A traditional clinical term for impaired copying, drawing or assembly of spatially organized material. Failures can involve spatial representations, neglect and planning rather than one general motor-program deficit.

Inaccurate visually guided reaching not adequately explained by elementary visual loss or weakness. Comparing gaze, hand and target conditions helps identify the affected visuomotor demands.^[ref]

A disproportionate failure to attend or respond to events on one side of space, often contralesional to brain injury. It may affect external space, the body or internally generated scenes and can occur without an equivalent primary visual-field loss.^[ref]

Researcher contributing to behavioural neuroscience.^[ref]

The relationship between neural activity and local vascular responses underlying many functional imaging measurements. Disease-related changes in this relationship complicate direct comparisons of activation magnitude.

Imaging a calcium-sensitive signal as an indirect measure related to cellular activity. Indicator kinetics, neuropil contributions and movement can affect its relationship to spikes.

Optical measurement of a fluorescent signal collected from a tissue volume. It can report population calcium or transmitter-sensor dynamics depending on the reporter; it is not automatically a single-neuron spike train.

An electrical response measured relative to a specified event, commonly estimated from repeated scalp recordings. Its timing and distribution constrain processing hypotheses, but scalp averages are not direct recordings from an isolated neural generator. Differences between conditions can overlap in time without demonstrating strictly separate serial stages.

A sustained lateralized electrophysiological signal during visual-memory delays, typically measured as a difference between signals contralateral and ipsilateral to the attended visual field. Its load dependence and relation to behavioral capacity constrain models without fixing a universal storage count.

Migraine is a neurological disorder that can be an outcome in a clinical trial or an observational study. Its statistical association with an exposure does not alone establish a causal effect.