office hours (M-3-551): Monday 3-4; Tuesday 11-12; or by appt.
Note: When all slides are not covered, they are rolled over to the next class. The first 18 slides were contained in the Jan 25 posting but not covered then.
Zeitgeist - general attitudes during a particular period of time
20th century - still some dualism. 21st century - ???? Current zeitgeist is that our nervous system represents an interaction between genetics and developmental experience. Nervous system control behavior which is also influenced by the immediate environment (the situation), and one’s interpretation of the situation.
Approaches to Examining Brain-Behavior Relationships
still study the behavioral characteristics of people with disease, disorder or injury
still manipulate brain anatomy or physiology and look at effects on behavior (surgery; drugs)
still examine at autopsy the brains of people of interest
still manipulate behavior and examine neurophysiological and anatomical changes, but through new techniques
Modern Imaging Tools
MRI - magnetic resonance imaging
fMRI - functional magnetic resonance imaging
PET scan - Positron Emission Tomography
Evoked Potentials - averaged EEG
MRI - 3 dimensional image of brain structure created by bouncing radio waves off of the brain’s hydrogen ions and recording inside a magnetic field
Fig 1: Conventional MRI of the human brain The subject is facing to the right (the nose is in the lower right), and this slice is taken straight down the middle of the brain. Note the remarkable anatomical detail.
Between sides Between front&back Between top&neck
fMRI - provides picture of cortical activity by measuring changes in oxygen levels in the brain which is an indicator of blood flow
PET scan - metabolic activity measured by glucose use. Inject with radioactive form of glucose, perform task, measure activity in specific brain areas
VISUAL AUDITORY PROBLEM SOLVING MEMORY MOTOR
Evoked Potentials - changes in EEG in response to stimulus processing. Can be done to examine response to sensory stimuli or brain activity while engaged in a cognitive task – a research tool. Offers msec by msec information about brain activity. Evoked potentials can also be recorded to examine sensory functioning – seeing, hearing, smelling. The normal waveforms and time of occurrence of are known and have been associated with the role of different parts of the sensory input system or brain. Can be used to determine if and why someone has a sensory problem. Established clinical diagnostic use.
Averaged across many trials Individual trials
Other new research tools:
manipulate genetics by creating a knock-out or knock-in mouse (without or with a certain gene) and examine effects
examine the neurochemistry of the brain through the use of radioactive antibodies or antibodies attached to a dye – labels a particular neurochemical and allows examination of how it is different across group or behavioral conditions under which it is used most
anesthetize or stimulate an area of the brain and see what happens (Wada technique; electrical stimulation)
single cell recording to determine what areas process what kind of stimuli (awake animals)