ORAC

What pattern do upper motor neurons involved in the control of axial muscles project to the spinal cord?

Medial gray matter over many spinal segments.

Which is true about population coding by primary motor cortical neurons?

The vector summation of population responses of primary motor cortical neurons is important for directional control of motor movements.

Which statement about 'mirror' motor neurons is false?

They fire in response to a specific motor act, irrespective of there being a behavioral goal associated with the act.

Which is not a function of the reticular formation?

Transmission of spinal nociceptive and tactile sensory signals to the cerebellum.

What is an anticipatory postural response of leg muscles whenever a person tugs on a handle called?

Feedforward motor control.

What role does the indirect pathway from the cortex to the spinal cord not play?

Post-injury recovery of fine motor functions such as using two fingers to pick up food.

What is the true statement about the reticular activating system?

It supports transitions between sleep and wakefulness.

What characterizes the acute phase of upper motor neuron syndrome?

The passive dropping of an affected limb that has been elevated and then released.

What is false about the Babinski sign?

It concerns normal versus abnormal flexion of the fingers.

What motor dysfunction would be expected in a patient with a tumor in the right internal capsule?

Left side paralysis (or severe weakness) of the lower face.

The cortical areas that plan and initiate motor sequences are comprised of what?

Several functionally distinct but highly interconnected regions.

Increased muscle tone and spasticity after upper motor neuron injury is partly due to what?

Increased responsiveness of motor neurons to Ia afferent inputs.

Which feature do corticospinal axons primarily exhibit?

They synapse onto spinal local circuit neurons.

What indicates the location of damage in a patient having difficulty sitting and standing without support?

D.

The anatomical structure that helped correct misconceptions about facial weakness deficits is which type of study?

Anatomical tract-tracing in primates.

What is a 'muscle field'?

The group of muscles whose activity is directly facilitated by a given upper motor neuron.

Which is false about primary motor cortex neurons?

The firing of primary motor cortical neurons occurs precisely at the onset of a muscle contraction.

What observation was made when Graziano stimulated cortical microstimulation in monkeys?

Purposeful movements distributed sequentially across multiple joints.

What does spike-triggered averaging correlate?

Upper motor neuron activity with muscle activation.

How does one typically visually examine a painting of a face?

By making many rapid eye movements, in different directions, acquiring information primarily during brief pauses at different locations on the object.

A patient who cannot perform anti-saccade most likely has sustained damage to which part?

B.

Which statement regarding saccadic eye movements is true?

Stimulation of particular upper motor neurons in the superior colliculus always produces a movement of the same magnitude and direction.

Which statement about the functions of the superior colliculus is false?

The uppermost layer of the SC is a somatotopic map that enables us to look at different locations on our body.

Lesions of the left frontal eye field would result in which observable condition?

Transient deviation of the eye to the left, plus a transient contralateral saccade deficit.

Where is neurological damage most likely found in a patient experiencing double vision with difficulty gazing forward or to the right?

In the left oculomotor nerve.

What disorder might a patient show with jerky smooth pursuit movements and difficulty fixating on a target?

Schizophrenia.

Which statement about sensorimotor integration in the SC is false?

The activation of neurons in the upper layers of the SC results in offset activation of lower-SC layers, producing a checkerboard pattern of upper-to-lower layer signaling.

Eye movements depend on what in the oculomotor commands?

The particular oculomotor neurons that are active and their firing rates.

Which structure is not involved in generating smooth pursuit movements?

All of the structures above are involved in the generation of smooth pursuit eye movements.

Where is damage typically found for vergence eye movements?

Extrastriate occipital regions.

In a patient with trouble abducting their left eye, what cranial nerve damage would you expect?

Damage to the left cranial nerve VI.

What aspects do vergence eye movements depend on?

All of the above.

Which nucleus innervates the superior oblique muscle?

Trochlear nucleus.

What possible additional symptom might a patient with inability to move their right eye toward the nose show?

Pupillary dilation in the right eye.

Among stabilized retinal images, which statement is false?

The fading of retinal images serves mainly to protect neurons in LGN and area 17 from photodamage.

What is not one of the basic types of eye movements?

Ptosis.

What type of eye movement occurs after 0.5 seconds in the given figure?

Smooth pursuit.

What maintains focal images constant on the retina during head shaking?

The vestibulo-ocular reflex.

What is a visual response that occurs when one diverts gaze from a television?

Accommodation of the lens.

What lobe is important for planning and selecting behavioral responses?

Frontal.

How does a right parietal lobe lesion affect attention?

Deficit in attention to the left side of the body or space.

What does the figure illustrate about attention controls by the two hemispheres?

D.

Which statement about neuronal responses in the temporal cortex of monkeys is true?

Norm-based tuning and population coding of objects.

What deficits would you expect with a right temporal lobe lesion?

Deficit in recognizing faces.

Where is damage likely in a teacher who struggles without shoe identification cues?

Right fusiform gyrus.

Which association cortex is involved in recognizing objects?

Temporal; frontal.

Which lobe is the largest in humans?

Frontal.

What does the delayed response task investigate?

Performance impairments in monkeys with bilateral prefrontal lesions.

What symptom would bilateral lesions in the dorsolateral prefrontal cortex produce?

Delayed or abolished success during the delayed response task.

How does neuropsychological testing function?

Allows for the systematic study of frontal lobe functions in humans.

Who generated cytoarchitectonic maps of the brain?

Korbinian Brodmann.

What was the leukotomy's purpose in the 1930s and 1940s?

Treatment for schizophrenia and other mental illnesses.

Which structure loses input if neocortical layer 6 output is blocked?

Thalamus.

What is true about the neocortex?

The archicortex includes the hippocampus.

If a gene in stellate neurons is knocked out, which layer is affected?

Layer 4.

What thalamic nuclei have inputs to association cortices?

Pulvinar; medial dorsal.

How do electrophysiological studies in primates benefit research?

Examine the responses of single cortical neurons in awake, behaving subjects.

How was information on the parietal lobe's role in selective attention obtained?

Rewarding monkeys for making correct choices.

Contralateral neglect syndrome arises from injury in which location?

Right posterior parietal cortex.

What is false about language?

Cortical areas used in sign language are largely different from those used in spoken language.

What is false about human handedness?

Currently there are surprisingly few left-handers among the elderly.

Which statement about lateralization of brain functions is true?

The prevalence of dominance suggests that lateralization of function maximizes use of the available neural circuitry.

What does anatomical asymmetry of the planum temporale demonstrate?

Is detectable in about two-thirds of humans.

Who developed the method of clinically assessing language lateralization?

John Wada.

What was Wilder Penfield's purpose for electrical stimulation of the cortex?

Mapping language functions with greater precision than previously accomplished.

Which statement about localization of language functions is false?

Neurons have been found that respond preferentially to a single, specific word.

What is the right hemisphere's likely role in language?

Processing the emotional and tonal (prosodic) components of language.

Which statement about language in the deaf is false?

Lesions of Wernicke's and Broca's areas produce deficits analogous to those caused by these lesions in hearing people.

Where would functional differences likely appear during reading between healthy controls and dyslexia patients?

Left occipito-temporal sulcus.

What disorder might be implicated if fMRI shows decreased activity in the left occipito-temporal sulcus?

Dyslexia.

What is the essential function of core cortical language areas?

Early processing of speech sounds.

Which statement about language capacities is true?

Primates use their left hemisphere to perceive affective tone in intraspecies communications.

What led to the initial discovery of language-specific cortical areas in humans?

Studies of patients with brain lesions.

What symptom do patients with left frontal cortex damage show?

Can understand language but cannot produce organized speech.

What is the role of the left temporal lobe in language?

Can produce words but have difficulty understanding language.

Which structure is essential for all vocalizations?

Larynx.

What are phonemes?

Basic speech sounds, in general.

What did Norman Geschwind confirm in the 1950s and 1960s?

Functions of Broca's and Wernicke's areas by making experimental lesions in humans.

What does the patient with right-hand holding a ball identify it as, but calls it a 'round thing' with left-hand indicate?

Is a split-brain patient.