Answers
What name is given to denote changes in electrical activity measured at
the scalp that are time-locked to a particular event or stimulus? Correct
Answer-Event-related potentials
What is typically recorded in the method of single-cell recording?
Correct Answer-The number of action potentials per second
Properties of the world that are manifested in cognitive and neural
systems are called Correct Answer-Representations
Which method is rarely used in humans? Correct Answer-Single-cell
recording
Why is an ERP signal from the thalamus virtually impossible to detect?
Correct Answer-It is too deep within the brain
What does the term P300 refer to? Correct Answer-A positive peak at
around 300 msec
Mental representation Correct Answer-the sense in which properties of
the outside world (e.g. colors, objects) are copied/stimulated by
cognition.
,Neural representation Correct Answer-The way in which properties of
the outside world manifest themselves in the neural signal
How Neurons Work - summation and parts of the neuron review Correct
Answer-Electrical input from MANY neurons is summed. If it exceeds a
threshold then the receiving neuron will also generate an action potential
What are the two main electrophysiological techniques? Correct
Answer-Single Cell Recording and Event-Related Potentials
Single Cell Recording Correct Answer-Electrode(s) are placed in or near
a neuron (invasive). They measure the number of action potentials per
second.
Event-Related Potentials Correct Answer-Electrodes are placed on the
skull to measure the summed electrical potential of millions of neurons
(sensitive to dendritic circuits)
Evidence of ________________ in vision. Correct Answer-hierarchical
organization
grandmother cell Correct Answer-A hypothesized type of neuron that
responds only to a very specific stimulus, such as a person's
grandmother. In theory this cell only responds to one specific stimulus
but they are controversial.
,Quiroga et al. (2005) Correct Answer-Studied single cell recordings in
the Medial Temporal Lobes of 8 epilepsy patients. They found a cell that
responded to the concept, face and name of a specific person but there
was no evidence this was the only cell responding or that the cell wasn't
responding more to general concepts.
Why not grandmother cells? Correct Answer-Cells respond to several
faces in a graded fashion and there is no evidence this is the only cell
responding.
Two Types of Structural Imaging Correct Answer-CT Scans or MRI's
Structural Imaging provides Correct Answer-detailed imagery of the
brain
CT Scan Correct Answer-are based on x-ray absorption in different
types of tissues. Based on density - bone shows white and cerebrospinal
fluid looks black.
MRI Correct Answer-based on magnetic field and radio. Can diagnose
tumors and find hemorrhaging.
2003 Nobel Prize to Mansfield & Lauterbur Correct Answer-for the
MRI
, Advantages of MRI over CT (brain) Correct Answer-MRI's do not use
radiation, better spatial resolution, better discrimination in white and
gray matter and can be used in fMRI.
Functional Imagining Correct Answer-Links brain STRUCTURE to
FUNCTION.
What are the two types of functional imagining? Correct Answer-PET
and fMRI's
Voxel-based morphometry (VBM) Correct Answer-a technique for
segregating and measuring differences in white matter and gray matter
concentration using 3D cubes called voxels.
PET scan (positron emission tomography) Correct Answer-Avisual
display of brain activity that detects where a radioactive form of glucose
goes while the brain performs a given task
fMRI (functional MRI) Correct Answer-A technique for revealing
bloodflow and, therefore, brain activity by comparing successive MRI
scans. _____ scans show brain function.
BOLD response Correct Answer-The change in blood oxygenation that
accompanies neural activity (BOLD = Blood Oxygen-Level Dependent)
Hemodynamic response function (HRF) Correct Answer-The change in
the BOLD response over time