Chapter 7 Flashcards
Functional Near-Infared Spectroscopy (fNIRS)
noninvasive technique that gathers light transmitted through cortical tissue to image blood-oxygen consumption, or oxygenated hemoglobin; form of optical tomography
Neuropsychology
study of the relations between brain function and behavior
Broca’s Area
8 or more similar cases and concluded that speech is located in the third frontal convolution of the left frontal lobe
Histological examination of brains
brains were sectioned postmortem and the tissue (histo) stained with differed dyes
Multiphoton Microscope
makes it possible to image living brain tissue in a three-dimensional view
Parkinson’s disease and the brain
early analysis of postmortem brain tissue showed that cells in the brainstem’s midbrain (substantia nigra) had died
What happens if the substantia nigra is killed experimentally?
animals showed symptoms similiar to Parkinson’s
Hippocampus
necessary for remembering the context in which we encounter information
What happens if you prevent the growth of new hippocampal neurons?
leads to memory deficits
Hippocampus & Behavior
cellular changes in the hippocampus and behavioral changes are closely linked; hippocampal neurons are necessary for contextual learning to take place
Ultimate function of any brain region?
produce behavior (movement)
Behavioral Neuroscience
study of the biological bases of behavior
Corsi Block-Tapping Test
requires participants to observe an experimenter tap a sequence of blocks. The test is to repeat the sequence correctly (subject does not see the #, but remember the location of the blocks tapped)
What does the Corsi test measure?
short-term recall of spatial position (block span)
What does span +1 measure?
reflects the learning and longer-term memory storage of information
Mirror-drawing task
requires a person to trace a pathway, such as a star, by looking in a mirror. Motor task initially prove quite difficult because movements in mirror are backwards, but improve with practice
How do people with memory problems do on mirror-drawing?
They may not remember ever completing the task before, but they too show improvement
Recency Memory Task
participants are shown a long series of cards, each bearing two stimulus items that are words or pictures. Sometimes a ? appears between them and they have to indicate if they have seen the items before and if so which item they saw most recently.
Place Learning
the rat must find the platform from any starting location in the pool. The only cues available are outside the pool so the rat must learn the relation between several cues in the room and the platform’s location
Matching-to-Place Learning
the rat has already learned that a platform always lies somewhere in the pool but is moved to a different location every day
Landmark Learning
the platform’s location is identified by a cue on the pool wall. The platform moves on every trial, but the relation to the cue is constant.
Ian Whishaw
has devised both novel tasks and novel scoring methods to measure the fine details of skilled reaching movements in rats
What does studying specific injuries in different regions tell us?
the function of the injured region AND what the remaining brain can do in the absence of the injured region
Karl Lashley
used ablation; trained monkeys and rats on mazes and motor tasks and then removed bits of cerebral cortex with the goal of producing amnesia for specific memories
What was the result of the Lashley studies?
memory loss was related to the amount of tissue he removed
Stereotaxic Apparatus
a device that permits a researcher or a neurosurgeon to target a specific part of the brain for ablation. The head is held in a fixed position, and because brain structures hold a fixed relationship with the location of the junction of the skull bones, it is possible to image a 3d map of the brain
Electrode Lesion
A small skull is drilled into the skull and an electrode is lowered into place. If a current is passed through the electrode the tissue in the region of the electrode tip is killed
Problems with electrolytic lesions
Neurons of the tissue and any nerve fibers passing through them are killed;
Neurotoxic Lesion
lower a narrow, metal tube (cannula) instead of an electrode, and infuse a neuron-killing chemical
Akinesia
slowness or absence of movement
L-Dopa
dopamine agonist; relieves Parkinson’s symptoms
Atropine
acetylcholine antagonist; relieves Parkinson’s symptoms
Rats with lateral hypothalamus stimulation
will eat when stimulated
Electrical self-stimulation
when animals learn to press a lever to obtain a current; stimulation is affecting a neural circuit that involves both eating and pleasure
Deep-brain stimulation
electrodes implanted in the brain stimulate a targeted area with a low-voltage electrical current to facilitate behavior
DBS and Parkinson’s
can help make movements smoother by stimulating the globus pallidus (basal ganglia)
Transcranial Magnetic Stimulation (TMS)
noninvasive technique; small wire coil is placed adjacent to the skull. A high voltage current is pulsed through the coil, which in turn produces a rapid increase and subsequent decrease in the magnetic field around the coil that passes through the skull and causes neurons to depolarize and fire; Can be used to either induce behavior or disrupt ongoing behavior