Term
| **Vertebrates have three categories of muscles. Name those three categories and briefly state what each type controls. |
|
Definition
1. smooth muscles, which control the digestive system and other organs.
2. skeletal, or striated, muscles, which control movement of the
body in relation to the environment. 3. cardiac muscles (the heart muscles), which have properties intermediate between those of smooth and skeletal muscles. |
|
|
Term
| *How does the ratio of axons to muscles fibers in a body part affect the precision of movement of that body part? |
|
Definition
Each muscle is composed of many fbers, illustrates. Although each muscle fiber receives information from only one axon, a given axon may innervate more than one muscle fiber. For example, the eye muscles have a ratio of about one axon per three muscle fibers, and the biceps muscles
of the arm have a ratio of one axon to more than a hundred fibers (Evarts, 1979). This diference allows the eye to move more precisely than the biceps. |
|
|
Term
| How do fast twitch and slow twitch fibers differ in the following: contractions, use of oxygen, fatigue, activity for which each kind is best suited. |
|
Definition
Our
muscle types range from fast-twitchfbers with fast contrac-
tions and rapid fatigue to slow-twitchfbers with less vigor-
ous contractions and no fatigue (Hennig & Lømo, 1985). We
rely on our slow-twitch and intermediate fbers for nonstren-
uous activities. For example, you could talk for hours without
fatiguing your lip muscles. You might walk for a long time, too.
But if you run up a steep hill at full speed, you switch to fast-
twitch fbers, which fatigue rapidly.Slow-twitch fbers do not fatigue because they are aerobic—
they use oxygen during their movements. You can think of
them as “pay as you go.” Prolonged use of fast-twitch fbers
results in fatigue because the process is anaerobic—using re-
actions that do not require oxygen at the time but need oxygen
for recovery |
|
|
Term
| Flexor muscle vs. extensor muscle |
|
Definition
| At your elbow, for example, your fexor muscle brings your hand toward your shoulder and your extensor muscle straightens the arm. |
|
|
Term
| muscle spindle vs. Golgi tendon organ |
|
Definition
One kind of proprioceptor is the musclespindle, a recep-
tor parallel to the muscle that responds to a stretch (Merton,
1972; Miles & Evarts, 1979). Whenever the muscle spindle is
stretched, its sensory nerve sends a message to a motor neuron
in the spinal cord, which in turn sends a message back to the
muscles surrounding the spindle, causing a contraction.
Golgitendonorgans, also proprioceptors, respond to in-
creases in muscle tension. Located in the tendons at opposite
ends of a muscle, they act as a brake against an excessively vig-
orous contraction. Some muscles are so strong that they could
damage themselves if too many fbers contracted at once.
Golgi tendon organs detect the tension that results during a
muscle contraction. |
|
|
Term
|
Definition
A neuromuscularjunction is a synapse between a mo-
tor neuron axon and a muscle fber. In skeletal muscles, every
axon releases acetylcholine at the neuromuscular junction,
and acetylcholine always excites the muscle to contract. |
|
|
Term
|
Definition
Mov-
ing a leg or arm back and forth requires opposing sets of
muscles, called antagonisticmuscles. At your elbow, for
example, your fexormuscle brings your hand toward your
shoulder and your extensor muscle straightens the arm |
|
|
Term
|
Definition
A proprioceptor (from the Latin proprius, meaning
one’s own) is a receptor that detects the position or move-
ment of a part of the body—in these cases, a muscle. Muscle
proprioceptors detect the stretch and tension of a muscle and
send messages that enable the spinal cord to adjust its signals. |
|
|
Term
|
Definition
One kind of proprioceptor is the musclespindle, a recep-
tor parallel to the muscle that responds to a stretch (Merton,
1972; Miles & Evarts, 1979). Whenever the muscle spindle is
stretched, its sensory nerve sends a message to a motor neuron
in the spinal cord, which in turn sends a message back to the
muscles surrounding the spindle, causing a contraction. Note
that this refex provides for negative feedback: When a muscle
and its spindle are stretched, the spindle sends a message that
results in a muscle contraction that opposes the stretch. |
|
|
Term
|
Definition
Te military distinguishes ballistic missiles from guided mis-
siles. A ballistic missile is launched like a thrown ball: Once
it is launched, no one can change its aim. A guided missile
detects the target and adjusts its trajectory to correct its aim.
Similarly, some movements are ballistic, and others are
corrected by feedback. A ballisticmovement is executed as a
whole: Once initiated, it cannot be altered. Refexes are ballistic,
for example. |
|
|
Term
| How does the posterior parietal cortex contribute to movement? What part of movement is difficult for people with damage to the posterior parietal cortex? |
|
Definition
Tis area keeps track of the position of the body relative to the
world.
with posterior parietal damage have trouble fnding objects in
space, even after describing their appearance accurately. When
walking, they frequently bump into obstacles (Goodale, 1996;
Goodale, Milner, Jakobson, & Carey, 1991). Beyond helping
to control aim, the posterior parietal cortex is also important
for planning movements. |
|
|
Term
| What does the prefrontal cortex contribute to movement? How are our actions in dreams similar to the actions of people with prefrontal cortex damage? |
|
Definition
Te prefrontalcortex, which is also active during a delay
before a movement, stores sensory information relevant to a
movement. It is also important for considering the probable
outcomes of possible movements.
If you had damage to this area, many of your move-
ments would be illogical or disorganized, such as showering
with your clothes on or pouring water on the tube of tooth-
paste instead of the toothbrush (M. F. Schwartz, 1995). In-
terestingly, this area is inactive during dreams, and the actions
we dream about doing are often as illogical as those of people
with prefrontal cortex damage |
|
|
Term
| What does the premotor cortex contribute to movement? When is it more active? Less active? |
|
Definition
Te premotorcortex is most active immediately before a
movement. It receives information about the target to which
the body is directing its movement, as well as information
about the body’s current position and posture (Hoshi & Tanji,
2000). Both kinds of information are, of course, necessary to
direct a movement toward a target. |
|
|
Term
| What does the supplementary motor cortex contribute to movement? What happens when supplementary motor cortex is lightly stimulated? What happens with longer or stronger stimulations? |
|
Definition
Te prefrontal cortex and the supplementarymotorcortex
are also important for planning and organizing a rapid sequence
of movements (Shima, Isoda, Mushiake, & Tanji, 2007; Tanji
& Shima, 1994). If you have a habitual action, such as turning
left when you get to a certain corner, the supplementary motor
cortex is essential for inhibiting that habit when you need to do
something else. |
|
|
Term
| *What are mirror neurons? What is their significance? |
|
Definition
active both dur-
ing preparation for a movement and while watching someone
else perform the same or a similar movement.
Tese neurons are theoreti-
cally exciting because of the idea that they may be important for
understanding other people, identifying with
them, and imitating them. For example, mirror
neurons in part of the frontal cortex become
active when people smile or see someone else
smile, and they respond especially strongly in people who report identifying strongly with other people |
|
|
Term
| **Which comes first, the decision to make a movement or the act of making the movement? Justify your answer with research evidence. |
|
Definition
Te key point is that the brain activity responsible for the
movement apparently began before the person’s conscious de-
cision! Te results seem to indicate that your conscious de-
cision does not cause your action. Rather, you become con-
scious of the decision after the process leading to action has
already been under way for about 300 ms. |
|
|
Term
| Describe the role of the cerebellum in movement. What are the symptoms of cerebellar damage? |
|
Definition
Responsible for balance.
One efect of cerebellar damage is trouble with rapid
movements that require aim, timing, and alternations of
movements. For example, people with cerebellar damage have
trouble tapping a rhythm, clapping hands, pointing at a mov-
ing object, speaking, writing, typing, or playing a musical in-
strument. |
|
|
Term
| Describe the role of the cerebellum in functions other than movement. |
|
Definition
a key role is to establish new mo-
tor programs that enable one to execute a sequence of ac-
tions as a whole. Inspired by this idea, many researchers
reported evidence that cerebellar damage impairs motor
learning. |
|
|
Term
| Briefly describe the nature of Parkinson’s disease? What is the immediate cause of the disease and its symptoms? How is Parkinson’s disease related to genetics? What environmental influences might be relevant? |
|
Definition
Te main symptoms of Parkinson’sdisease (also known as
Parkinson disease) are rigidity, muscle tremors, slow move-
ments, and difculty initiating physical and mental activity
(M. T. V. Johnson et al., 1996; Manfredi, Stocchi, & Vacca,
1995; Pillon et al., 1996). It strikes about 1% to 2% of people
over age 65. In addition to the motor problems, patients are
slow on cognitive tasks, such as imagining events or actions,
even when they don’t have to do anything (Sawamoto, Honda,
Hanakawa, Fukuyama, & Shibasaki, 2002). A loss of olfac-
tion is often an early symptom, and sometimes the frst symp-
tom (Wattendorf et al., 2009). Depression and memory loss
are also common symptoms, beginning early in the course of
the disease (Ouchi et al., 1999).
Te basal ganglia have cells specialized for learning to
start or stop a voluntary sequence of motions (Jin & Costa,
2010). Tose cells are impaired in Parkinson’s disease, and the
result is a difculty with spontaneous movements in the ab-
sence of stimuli to guide their actions.
Te immediate cause of Parkinson’s disease is the gradual pro-
gressive death of neurons.
No one supposes that Parkinson’s disease often results
from using illegal drugs. A more likely hypothesis is that
people are sometimes exposed to hazardous chemicals in
herbicides and pesticides (Figure 8.21), many of which dam-
age cells of the substantia nigra (Hatcher, Pennell, & Miller,
2008). Parkinson’s disease is more common than average
among farmers and others who have had years of exposure
to herbicides and pesticides
who smoke cigarettes or drink cofee have less chance of
developing Parkinson’s disease |
|
|
Term
| Why is L-dopa effective in treating Parkinson’s patients, but not dopamine? |
|
Definition
A dopamine
pill would be inefective because dopamine does not cross the
blood–brain barrier. L-dopa, a precursor to dopamine, does
cross the barrier. Taken as a daily pill, L-dopa reaches the
brain, where neurons convert it to dopamine. L-dopa is the
main treatment for Parkinson’s disease. |
|
|
Term
| Briefly describe the nature of Huntington’s disease. Include a description of its genetic basis. |
|
Definition
Motor symptoms usually begin with arm jerks
and facial twitches. Ten tremors spread to other parts of
the body and develop into writhing (M. A. Smith, Brandt, &
Shadmehr, 2000). (Chorea comes from the same root as chore-
ography. Te rhythmic writhing of chorea resembles dancing.)
Gradually, the tremors interfere more and more with walking,
speech, and other voluntary movements. Te ability to learn
and improve new movements is especially limited (Willing-
ham et al., 1996). Te disorder is associated with gradual,
extensive brain damage, especially in the caudate nucleus,
putamen, and globus pallidus but also in the cerebral cortex
People with Huntington’s disease also sufer psychological
disorders, including depression, sleep disorders, memory im-
pairment, anxiety, hallucinations and delusions, poor judgmentalcoholism, drug abuse, and sexual disorders ranging from com-
plete unresponsiveness to indiscriminate promiscuity
Huntington’s disease results from a dominant gene on chro-
mosome #4. As a rule, a mutant gene that causes the loss of
a function is recessive. Te fact that the Huntington’s gene is
dominant implies that it produces the gain of some undesir-
able function. |
|
|
Term
| *Why did psychologists in the early to mid-part of the 20th century resist the notion that wake and sleep cycles are generated from within the body? |
|
Definition
When behaviorism dominated experimental
psychology during the mid-1900s, many psychologists
believed that every behavior could be traced to external
stimuli. For example, alternation between wakefulness and
sleep must depend on something in the outside world, such as
changes in light or temperature. Research as early as that of
Curt Richter (1922) implied that the body generates its own
cycles of activity and inactivity, but it took a huge amount of
research to convince the skeptics. Te idea of self-generated
rhythms was a major step toward viewing animals as active
producers of behaviors. |
|
|
Term
| What is an endogenous rhythm? Why are endogenous rhythms important for animals, including humans? |
|
Definition
Animals’ readiness for a change in seasons comes partly
from internal mechanisms. |
|
|
Term
How long is the rhythm period generated by the human
circadian clock when it has no external cue to set it? |
|
Definition
| we find it difficult to sleep on anything far from a 24-hour schedule. |
|
|
Term
| List five zeitgebers that function to reset circadian rhythm. Which is the dominant zeitgeber for land animals? |
|
Definition
Te stimulus that resets the circadian rhythm
is referred to by the German term zeitgeber (TSITE-gay-
ber), meaning “time-giver.” Light is the dominant zeitgeber
for land animals (Rusak & Zucker, 1979). (Te tides are
important for many marine animals.) In addition to light,
other zeitgebers include exercise (Eastman, Hoese, Young-
stedt, & Liu, 1995), arousal of any kind (Gritton, Sutton,
Martinez, Sarter, & Lee, 2009), meals, and the temperature
of the environment. |
|
|
Term
| Endogenous circannual rhythm vs. endogenous circadian rhythms |
|
Definition
endogenouscircan-
nualrhythm. (Endogenous means “generated from within.”
Circannual comes from the Latin words circum, for “about,”
and annum, for “year.”)(YEARLY CYCLE)
endogenouscircadianrhythms
that last about a day. (Circadian comes from circum, for
“about,” and dies, for “day.”(DAILY CYCLE) |
|
|
Term
|
Definition
| The stimulus that resets the circadian rhythm |
|
|
Term
|
Definition
the retinohypotha-
lamic path to the SCN comes from a special population
of retinal ganglion cells that have their own photopigment,
called melanopsin |
|
|
Term
|
Definition
Sleep is a state that the brain
actively produces, characterized by decreased response to
stimuli |
|
|
Term
|
Definition
coma (KOH-muh) is an extended period
of unconsciousness caused by head trauma, stroke, or disease.
It is possible to awaken a sleeping person but not someone
in a coma. A person in a coma has a low level of brain activ-
ity throughout the day, and little or no response to stimuli,
including those that are ordinarily painful. |
|
|
Term
|
Definition
Someone in a vegetativestate alternates between peri-
ods of sleep and moderate arousal, although even during the
more aroused state, the person shows no awareness of sur-
roundings. Breathing is more regular, and a painful stimu-
lus produces at least the autonomic responses of increased
heart rate, breathing, and sweating. Te person does not
speak, respond to speech, or show any purposeful activity. |
|
|
Term
| Minimally conscious state |
|
Definition
A minimallyconsciousstate is onestage higher, with occasional, brief periods of purposeful
actions and a limited amount of speech comprehension. A
vegetative or minimally conscious state can last for months
or years. |
|
|
Term
|
Definition
Braindeath is a condition with no sign of brain activity
and no response to any stimulus. Physicians usually wait un-
til someone has shown no sign of brain activity for 24 hours
before pronouncing brain death, at which point most people
believe it is ethical to remove life support. |
|
|
Term
| **Describe how humans progress through the stages of non-Rem and Rem sleep throughout the night. When is REM sleep predominant? On what does the amount of REM depend? |
|
Definition
stage 1 sleep, the EEG is dominated by irregular, jag-
ged, low-voltage waves. Overall brain activity is less than in re-
laxed wakefulness but higher than other sleep stages. the most prominent characteristics of stage 2
are sleep spindles and K-complexes. A sleepspindle consists
of 12- to 14-Hz waves during a burst that lasts at least half a
second. Sleep spindles result from oscillating interactions be-
tween cells in the thalamus and the cortex.. A K-complex is sharp wave associated with temporary inhibition of neuronal
fring.
In the succeeding stages of sleep, heart rate, breathing
rate, and brain activity decrease, while slow, large-amplitude
waves become more common. stage 4, more than half the record includes large waves of at
least a half-second duration. Stages 3 and 4 together constitute
slow-wavesleep(SWS). |
|
|
Term
| What is the relationship between REM sleep and dreaming? |
|
Definition
In short, REM and dreams usu-
ally overlap, but they are not the same thing. |
|
|
Term
| What is paradoxical about paradoxical sleep? |
|
Definition
paradoxicalsleep because it is deep sleep in some ways and light in others.
(The term paradoxical means “apparently self-contradictory.”) |
|
|
Term
| *What happens to human motor function during REM sleep? |
|
Definition
Activity decreased in the primary visual cortex, the
motor cortex, and the dorsolateral prefrontal cortex but in-
creased in parts of the parietal and temporal cortex |
|
|
Term
|
Definition
|
|
Term
|
Definition
impaired ability to
breathe while sleeping. People with sleep apnea have breath-
less periods of a minute or so from which they awaken gasp-
ing for breath. Tey may not remember all their awakenings,
although they certainly notice the consequences—sleepiness
during the day, impaired attention, depression, and some-
times heart problems. |
|
|
Term
|
Definition
a condition characterized by frequent periods
of sleepiness during the day |
|
|
Term
|
Definition
A sleepspindle consists
of 12- to 14-Hz waves during a burst that lasts at least half a
second. Sleep spindles result from oscillating interactions be-
tween cells in the thalamus and the cortex. |
|
|
Term
|
Definition
REM sleep is associated with a distinctive pattern of
high-amplitude electrical potentials known as PGOwaves,
for pons-geniculate-occipital (Figure 9.15). Waves of neu-
ral activity are detected frst in the pons, shortly afterward
in the lateral geniculate nucleus of the thalamus, and then
in the occipital cortex (D. C. Brooks & Bizzi, 1963; Lau-
rent, Cespuglio, & Jouvet, 1974). Each animal maintains a
nearly constant amount of PGO waves per day. |
|
|
Term
| **Name the five important functions of sleep listed by Kalat. What likely hypothesis is given by Kalat for the original function of sleep? |
|
Definition
During sleep, we rest our mus-
cles, decrease metabolism, rebuild proteins in the brain (Kong
et al., 2002), reorganize synapses, and strengthen memories
(Sejnowski & Destexhe, 2000). People who don’t get enough
sleep have trouble concentrating and become more vulnerable
to illness, especially mental illness.
Sleep conserves en-
ergy during the inefcient times, when activity would be
wasteful and possibly dangerous. |
|
|
Term
| Discuss the relationship between sleep and memory, including REM sleep. |
|
Definition
Another apparent function of sleep is improved
memory. Young adults deprived of a night’s sleep
show defcits on memory tasks (Yoo, Hu, Gujar,
Jolesz, & Walker, 2007). In contrast, if people learn
something and then go to sleep, or even take a nap,
their memory often improves beyond what it was
before the sleep.
Patterns that
occurred during sleep resembled those that occurred dur-
ing learning, except that they were more rapid during sleep.
Furthermore, the amount of hippocampal activity during
sleep correlated highly with the subsequent improvement in
performance.
One hypothesis is that REM is
important for memory storage, es-
pecially for weakening the inappro-
priate connections |
|
|
Term
| **Discuss the biological functions of REM sleep, including David Maurice’s hypothesis related to eye movements. |
|
Definition
David Maurice (1998)
proposed that REM just shakes the eyeballs back and forth
enough to get sufcient oxygen to the corneas of the eyes. Te
corneas, unlike the rest of the body, get oxygen directly from the
surrounding air. During sleep, because they are shielded from
the air, they deteriorate slightly |
|
|
Term
| Activation synthesis hypothesis vs. clinic-anatomical hypothesis |
|
Definition
According to the activation-synthesishypothesis, a dream
represents the brain’s efort to make sense of sparse and distorted information. to Like the activation-synthesis theory,
this theory emphasizes that dreams begin with arousing
stimuli that are generated within the brain combined with
recent memories and any information the brain is receiving
from the senses. However, the clinico-anatomical hypoth-
esis puts less emphasis on the pons, PGO waves, or REM
sleep. It regards dreams as thinking that takes place under
unusual conditions, similar to mind-wandering during ev-
eryday life |
|
|
Term
| *Biologically speaking, what is necessary for life? |
|
Definition
Biologically, the necessary
condition for life is a coordinated set of chemical reactions. |
|
|
Term
Why do birds stand on one leg, vultures sometimes defecate onto their own legs, Australian geckos sometimes huddle together, infant rats sometimes appear learning deficient, and female rats learn best during their fertile
period? |
|
Definition
|
|
Term
| What is the primary advantage of maintaining a consistent high body temperature? Given that advantage, why did we evolve a body temperature of 37 degrees centigrade instead of a warmer value? |
|
Definition
From the standpoint of
muscle activity, we gain an advantage by being as warm as pos-
sible. A warmer animal has warmer muscles and therefore runs
faster with less fatigue than a cooler animal.
maintaining a higher temperature requires more fuel and energy. Second, and more importantly,
beyond about 40° or 41° C, proteins begin to break their
bonds and lose their useful properties. |
|
|
Term
| Describe what happens when humans have a fever. What good does fever do? When is fever damaging? |
|
Definition
Certain types of bacteria grow
less vigorously at high temperatures than at normal mamma-
lian body temperatures. Also, fever enhances activity of the
immune system (Skitzki, Chen, Wang, & Evans, 2007). Other
things being equal, developing a moderate fever probably in-
creases an individual’s chance of surviving a bacterial infec-
tion (Kluger, 1991). However, a fever above about 39° C (103°
F) in humans does more harm than good, and a fever above
41° C (109° F) is life-threatening (Rommel et al., 1998). |
|
|
Term
| Homeostasis vs. allostasis |
|
Definition
homeostasis (HO-mee-oh-STAY-sis) to refer to tempera-
ture regulation and other biological processes that keep body
variables within a fxed range.
allostasis
(from the Greek roots meaning “variable” and “standing”),
which means the adaptive way in which the body changes its
set points depending on the situation. |
|
|
Term
| Poikilothermic vs. homeothermic |
|
Definition
Amphibians, reptiles, and most fsh are poikilothermic
(POY-kih-lo-THER-mik, from Greek roots meaning “varied
heat”). Tat is, their body temperature matches the tempera-
ture of their environment.
Mammals and birds are homeothermic(from Greek roots
meaning “same heat”), except that certain species become poiki-
lothermic during hibernation. Homeothermic animals use phys-
iological mechanisms to maintain a nearly constant body tem-
perature despite changes in the temperature of the environment. |
|
|
Term
|
Definition
a single value that the body
works to maintain. |
|
|
Term
|
Definition
|
|
Term
|
Definition
attack the intruders. Cytokines
also stimulate the vagus nerve, which sends signals to the hypo-
thalamus (Ek et al., 2001; Leon, 2002), increasing the release of
chemicals called prostaglandins. |
|
|
Term
| **Explain the biological advantages for sexual reproduction that requires two individuals to mate. |
|
Definition
Biologists’ explanation is that sexual reproduction in-
creases variation and thereby enables quick evolutionary ad-
aptations to changes in the environment.
Sex also cor-
rects errors: If you have a disadvantageous mutation in one
gene and your mate has a disadvantageous mutation in a difer-
ent gene, your children could have a normal copy of both genes. |
|
|
Term
| What is the relationship between cholesterol and steroid hormones? |
|
Definition
From then on, the male’s testes produce more androgens
than estrogens (hormones that are more abundant in females).
Te female’s ovaries produce more estrogens than androgens.
Androgens and estrogens are steroidhormones, containing four
carbon rings, derived from cholesterol
We are
often warned about the risks of excessive cholesterol, but a mod-
erate amount is necessary for generating these important hor-
mones. |
|
|
Term
| Name three ways steroids exert their effects. |
|
Definition
First, they bind to membrane receptors, like
neurotransmitters, exerting rapid efects. Second, they enter cells
and activate certain kinds of proteins in the cytoplasm. Tird,
they bind to receptors that bind to chromosomes, where they
activate or inactivate certain genes |
|
|
Term
Describe the steps in the normal prenatal development of the female and male reproductive structures. How does the development of genitalia
differ from the development of the internal reproductive structures? |
|
Definition
A high level of testosterone causes
the external genitals to develop the male pattern, and a low
level leads to the female pattern. Estradiol produces impor-
tant efects on the internal organs, but it has little efect on the
external genitals. |
|
|
Term
| Outline the body parts/functions controlled by the left and the right hemispheres of the human brain; e.g., left hemisphere is connected to skin receptors and muscles mainly on the right side of the body. |
|
Definition
For most people, the left hemisphere is specialized for
language and analytical processing. Te right hemisphere
is specialized for certain complex visuospatial tasks and
synthetic processing.
Te left hemisphere of the cerebral cortex is connected to skin
receptors and muscles mainly on the right side of the body. Te
right hemisphere is connected to skin receptors and muscles
mainly on the left side. As an exception to this rule, both hemi-
spheres control the trunk muscles and facial muscles. |
|
|
Term
| Which two sets of sensory receptors are controlled by the ipsilateral hemisphere rather than the contralateral hemisphere? |
|
Definition
|
|
Term
| *The human brain has bilateral control of which two sets of muscles? |
|
Definition
both hemi-
spheres control the trunk muscles and facial muscles. |
|
|
Term
| Describe the organization of visual and auditory connections to the hemispheres. How is the auditory system organized differently than the visual system? |
|
Definition
the left hemisphere
sees the right side of the world, and the right hemisphere sees the left side.
The auditory system is organized diferently. Each ear sends
the information to both sides of the brain, because any brain
area that contributes to localizing sounds must compare input
from both ears. However, each hemisphere does pay more at-
tention to the ear on the opposite side |
|
|
Term
| Why is lateralization of function between the two hemispheres observed more easily in split-brain people than in intact brain people? |
|
Definition
| Because the brain no longer has connections between the lobes and behaviors are not communicated between lobes. |
|
|
Term
| Describe the effects of severing the corpus callosum of people with epilepsy, other than a reduction in quantity and severity of seizures. |
|
Definition
. Evidently, epileptic activity rebounds back and
forth between the hemispheres and prolongs seizures. If it
can’t bounce back and forth across the corpus callosum, a sei-
zure may not develop at all. |
|
|
Term
| Subjects with left hemisphere damage are better than subjects with intact brains at judging whether videotaped speeches are truth or lies. Explain this finding. |
|
Definition
Tey only poorly understood the speech, but they were
adept at reading gestures and facial expressions. |
|
|
Term
| *According to Robert Ornstein, how is the difference in functions between the hemispheres best described? |
|
Definition
According to Robert Ornstein (1997), the left hemisphere
focuses more on details and the right hemisphere more on
overall patterns. |
|
|
Term
| Describe the development (maturation) of the corpus callosum over the first 5 to 10 years of human life. |
|
Definition
Te corpus callosum gradually grows and thickens as myelin
increases around certain axons during childhood and adoles-
cence |
|
|
Term
| *In what way is human language different from the communication displays of other animals? |
|
Definition
Human
language stands out from other forms of communication
because of its productivity—its ability to improvise new
combinations of signals to represent new ideas. |
|
|
Term
| **Give three likely explanations for why bonobo chimpanzees, Kanzi and Malika, developed more impressive language skills than other chimpanzees. |
|
Definition
Perhaps bonobos have more
language potential than common chimpanzees. A second ex-
planation is that Kanzi and Mulika began language training
when young. A third reason pertains to the method of train-
ing: Perhaps learning by observation and imitation promotes
better understanding than the formal training methods of
previous studies |
|
|
Term
| Briefly discuss the concept of a language acquisition device. |
|
Definition
Noam
Chomsky (1980) and Steven Pinker (1994) proposed that
humans have a languageacquisitiondevice, a built-in
mechanism for acquiring language. |
|
|
Term
| Compare the language difficulties experienced by people with Broca’s aphasia to those with Wernicke’s aphasia. |
|
Definition
When people with brain damage sufer impaired language
production, we call it Broca’saphasia, or nonfuentaphasia,
regardless of the exact location of damage.
Damage in and around
Wernicke’sarea (Figure 14.14), located near the audi-
tory cortex, produces Wernicke’saphasia, characterized
by poor language comprehension and impaired ability to
remember the names of objects. It is also known as fluent
aphasia because the person can still speak smoothly |
|
|
Term
| Describe the main functional problems that contribute to reading difficulties in dyslexia. |
|
Definition
Dyslexia is a specifc impairment of reading in someone
with adequate vision, adequate motivation, and adequate
overall cognitive skills. It is more common in boys than girls
and has been linked to at least four genes that produce def-
cits in hearing or cognition
dyslexia occurs in all languages and always
pertains to a difculty converting symbols into sounds |
|
|
Term
| Describe the different causes and mechanisms of osmotic and hypovolemic thirst. |
|
Definition
We distinguish two types of thirst. Eating salty foods causes
osmotic thirst, and losing fuid by bleeding or sweating induces
hypovolemic thirst. |
|
|
Term
| *Who would drink more pure water-somene with osmotic thirst or someone with hypovolemic thirst? |
|
Definition
Whereas an animal with osmotic thirst needs water, one
with hypovolemic thirst can’t drink much pure water. If it did,
it would dilute its body fuids. It therefore increases its pref-
erence for slightly salty water |
|
|
Term
| **Trace the process of digestion through the human body. Where does it start? What occurs in the stomach, the small intestine, and the large intestine? |
|
Definition
Digestion begins in the mouth, where enzymes in the
saliva break down carbohydrates. Swallowed food travels down
the esophagus to the stomach, where it mixes with hydrochloric
acid and enzymes that digest proteins. Te stomach stores food
for a time, and then a round sphincter muscle opens at the end of
the stomach to release food to the small intestine.Te small intestine has enzymes that digest proteins, fats,
and carbohydrates. It is also the site for absorbing digested
materials into the bloodstream. Te blood carries those chem-
icals to body cells that either use them or store them for later
use. Te large intestine absorbs water and minerals and lubri-
cates the remaining materials to pass as feces. |
|
|
Term
| **Trace the process of digestion through the human body. Where does it start? What occurs in the stomach, the small intestine, and the large intestine? |
|
Definition
Digestion begins in the mouth, where enzymes in the
saliva break down carbohydrates. Swallowed food travels down
the esophagus to the stomach, where it mixes with hydrochloric
acid and enzymes that digest proteins. Te stomach stores food
for a time, and then a round sphincter muscle opens at the end of
the stomach to release food to the small intestine.Te small intestine has enzymes that digest proteins, fats,
and carbohydrates. It is also the site for absorbing digested
materials into the bloodstream. Te blood carries those chem-
icals to body cells that either use them or store them for later
use. Te large intestine absorbs water and minerals and lubri-
cates the remaining materials to pass as feces. |
|
|
Term
| What does the stomach contribute to satiety? How does the stomach convey satiety messages to the brain? |
|
Definition
Te stomach conveys satiety messages to the brain via
the vagus nerve and the splanchnic nerves. Te vagusnerve
(cranial nerve X) conveys information about the stretching
of the stomach walls, providing a major basis for satiety.
Te splanchnic (SPLANK-nik) nerves convey informa-
tion about the nutrient contents of the stomach. |
|
|
Term
| What part of the digestive process occurs in the duodenum? |
|
Definition
Te duodenum (DYOU-oh-DEE-num or
dyuh-ODD-ehn-uhm) is the part of the small intestine ad-
joining the stomach. It is the frst digestive site that absorbs a
signifcant amount of nutrients. |
|
|
Term
| Describe the insulin and glucagon feedback system. What is the effect of steadily high insulin levels on feeding? |
|
Definition
When glucose levels rise, the pancreas releases the hormone in-
sulin, which causes cells to store the excess glucose as fats and
glycogen. The entry of glucose into cells suppresses hunger and
decreases eating, thereby lowering the glucose level.
effects of steady high insulin levels on
feeding
Constantly high insulin causes blood glucose to be stored as fats
and glycogen. Because it becomes diffcult to mobilize the stored
nutrients, hunger returns soon after each meal. |
|
|
Term
| Where is leptin produced? What does leptin do? |
|
Definition
the body’s fat
cells produce leptin: Te more fat cells, the more leptin.
Leptin signals your brain about your fat reserves, providing
a long-term indicator of whether you have been overeating or
undereating. Each meal also releases leptin, so the amount of
circulating leptin indicates something about short-term nutri-
tion as well. Animal studies show that when leptin levels are
high, you act as if you have plenty of nutrition. You eat less
(Campfeld, Smith, Guisez, Devos, & Burn, 1995), become
more active |
|
|
Term
| **Describe the genetic and environmental influences that have contributed to the seriously overweight condition of many Native American Pima of Arizona and Mexico. |
|
Definition
Most are seriously
overweight, apparently because of several genes (Norman
et al., 1998). However, obesity was uncommon among them
in the early 1900s, when their diet consisted of desert plants
that ripen in the brief rainy season. Te Pima apparently
evolved a strategy of eating all they could when food was avail-
able because it would have to carry them through periods of
scarcity. Tey also evolved a tendency to conserve energy by
limiting their activity. Now, with a more typical U.S. diet that
is equally available at all times, the strategy of overeating and
inactivity is maladaptive. |
|
|
Term
| *Describe how diet soft drinks may contribute to obesity rather than helping control weight. |
|
Definition
Tey learned that taste is a poor predictor
of energy, and so they overate other foods and stopped com-
pensating afterward. Tey also became less active |
|
|
Term
| **Describe some objections to the notion that evolution has predisposed men more than women to be more interested in multiple mates |
|
Definition
One objection is that a woman does sometimes gain from
having multiple sex partners (Hrdy, 2000). If her husband is
infertile, mating with another man could be her only way of
reproducing. Also, another sexual partner may provide aid of
various sorts to her and her children. In addition, she has the
possibility of “trading up,” abandoning her frst mate for a bet-
ter one. So the prospect of multiple mates may be more ap-
pealing to men, but it has advantages for women, too. Human
cultures vary substantially in how well they tolerate women
having multiple sexual partners.
Another objection is that researchers have no direct evi-
dence that genes infuence people’s preferences for one mate
or many. |
|
|
Term
| Describe the role of dopamine during sexual activity |
|
Definition
MPOA neurons re-
lease dopamine strongly during sexual activity, and the more
dopamine they release, the more likely the male is to copulate
n moderate concentrations, dopamine stimulates mostly
type D1 and D5 receptors, which facilitate erection of the penis
in the male (Hull et al., 1992) and sexually receptive postures
in the female (Apostolakis et al., 1996). In higher concentra-
tions, dopamine stimulates type D2 receptors, which leads
to orgasm. |
|
|
Term
| Give two explanations for the finding that married men and men living in a committed relationship with a wman, tend to have lower testosterone levels than single uncommited men. |
|
Definition
The apparently obvious interpretation was that
once a man established a lasting relationship, he no longer
needed to work so hard to seek a sexual partner, and his tes-
tosterone levels dropped. However, that study did not tell us
which came frst, the committed relationship or the lower tes-
tosterone level. Another study found that men’s testosterone
levels did not change after marriage. Instead, men with lower
testosterone levels were more likely to marry than were men
with high testosterone levels (van Anders & Watson, 2006).
Similar studies found that single women had higher testoster-
one levels than women with a long-term partner, either ho-
mosexual or heterosexual |
|
|
Term
| What is a common cause for a genetic female (XX) to develop a partly masculinized anatomy? |
|
Definition
some people are born with an XX chromosome
pattern but an SRY gene that translocated from the father’s
Y chromosome onto another chromosome. Despite their XX
chromosomes, they have either an ovary and a testis, or two
testes, or a mixture of testis and ovary tissue on each side. |
|
|
Term
| Describe some of the evidence that genetic factors may influence sexual orientation and name some physical and behavioral differences between homosexual and heterosexual people. |
|
Definition
On average, heterosexual men are
slightly taller and heavier than homosexual men.
Tat is, if one
twin is homosexual, the probability for the other to be homo-
sexual is fairly high for a monozygotic twin, and less high for
a dizygotic twin.
Several studies reported a higher incidence of homosexual-
ity among the maternal than paternal relatives of homosexual
men.
According to a second hypothesis, genes that produce ho-
mosexuality in males produce advantageous efects in their sis-
ters and other female relatives, increasing their probability of
reproducing and spreading the genes. Te results of one study
support this hypothesis. Homosexual men’s mothers and aunts
had a greater than average number of chA third hypothesis is that certain genes lead to homosexu-
ality in men homozygous for the gene but produce reproduc-
tive advantages in men heterozygous for the gene.
Te most prominent hypothesis
is that a mother’s immune system sometimes reacts against
a protein in a son and then attacks subsequent sons enough
to alter their development.
On average, homosexual men are shifted
partly in the female-typical direction for some brain struc-
tures but not others. Similarly, on average, homosexual wom-
en’s brains are slightly shifted in the male direction in some
ways but not others. |
|
|
Term
| organizing effets of sex hormones vs. activating effects of sex hormones |
|
Definition
Organiz-
ingefects produce long-lasting structural efects. Te most
prominent organizing efects occur during a sensitive stage
of early development—shortly before and after birth in rats
and well before birth in humans—determining whether the
body develops female or male anatomy.
Activatingefects
are more temporary, when a hormone increases some activ-
ity that lasts only while the hormone is present. Activating
efects occur at any time in life. |
|
|
Term
| sex differences vs. gender differences |
|
Definition
| sex differences are anatomical differences whereas gender differences are how the person relates to their gender. |
|
|
Term
| mullerian ducts vs. Wolffian ducts |
|
Definition
Male and female mammals start with the same anatomy
during an early stage of prenatal development. Both have a
set of Müllerianducts(precursors to female internal struc-
tures) and a set of Wolfan ducts (precursors to male inter-
nal structures) |
|
|
Term
| sexually dimorphic nucleus |
|
Definition
one area in the anterior hypothala-
mus, known as the sexuallydimorphicnucleus, is larger
in males than in females and contributes to control of male
sexual behavior. |
|
|
Term
|
Definition
Some people have anatomies intermediate between male and
female (Haqq & Donahoe, 1998). Individuals who appear to
be a mixture of male and female are referred to ashermaph-
rodites (from Hermes and Aphrodite in Greek mythology).
For example, some people are born with an XX chromosome
pattern but an SRY gene that translocated from the father’s
Y chromosome onto another chromosome. Despite their XX
chromosomes, they have either an ovary and a testis, or two
testes, or a mixture of testis and ovary tissue on each side. |
|
|
Term
| congenital adrenal hyperplasia |
|
Definition
overdevelopment of the
adrenal glands from birth which can cause a person to have an appearance of the opposite sex. |
|
|
Term
| Name and give an example f each of the three components usually included in a psychologist's definition of emotion. Which of these components is the most central to our concept of emotions? explain |
|
Definition
psychologists generally agree that emotion has
three components—cognitions (“Tis is a dangerous situa-
tion”), feelings (“I feel frightened”), and actions (“Run for the
nearest exit”). Of these, feelings are the most central to our
concept of emotion. |
|
|
Term
| What are the roles of the two branches of the autonomic nervous system in emotinal arousal? |
|
Definition
the sympathetic and the parasym-
pathetic (Figure 12.1). Walter Cannon was the frst to under-
stand that the sympathetic nervous system prepares the body
for brief, vigorous “fght-or-fight” responses. Te parasympa-
thetic nervous system increases digestion and other processes
that save energy and prepare for later events. |
|
|
Term
| **Describe the James-Lange theory of emotional arousal. To what extent has this theory held up over time? State the evidence. |
|
Definition
the autonomic arousal and skeletal actions
come frst. What you experience as an emotion is the label you
give to your responses: You feel afraid because you run away;
you feel angry because you attack.
In a later paper, William James (1894) clarifed
his position. An emotion has three components: cognitions,
actions, and feelings. Te cognitive aspect comes frst. You
quickly appraise something as good, bad, frightening, or what-
ever. Your appraisal of the situation leads to an appropriateaction, such as running away, attacking, or sitting motionless
with your heart racing. When William James said that arousal
and actions led to emotions, he meant the feeling aspect of an
emotion. That is,
If a feeling is a kind of sensation, it is hard to know where
the sensation would come from if not from some change in
the body
James-Lange Theory:
Event
Appraisal (the cognitive aspect)
Action (the behavioral aspect including physiology)
Emotional feeling (the feeling aspect) |
|
|
Term
| *The results of brain scans in research trying to pinpoint which parts of the brain are activated by which emotion depend more on the details of the procedure than the emotion studied--with one exception. Which emotion does seem t be localized? Where? |
|
Definition
Of all emotions, only disgust seems to be associated with
the response of a particular brain area. Te insular cortex,
or insula, is strongly activated if you see a disgusting picture
(F. C. Murphy, Nimmo-Smith, & Lawrence, 2003; M. L. Phil-
lips et al., 1997) or the facial expression of someone who is feel-
ing disgusted |
|
|
Term
| If brain damage impairs someone's emotions, what happens to the person's decision making? |
|
Definition
Damage to parts of the prefrontal cortex blunts people’s emo-
tions in most regards, except for an occasional outburst of an-
ger. It also impairs decision making. People with such damage
often make impulsive decisions without pausing to consider
the consequences, including how they will feel after a possible
mistake. When given a choice, they frequently make a quick
decision and then immediately sigh or wince, knowing that they have made the wrong choice |
|
|
Term
| *What happened when young women were given testosterone injections before identifying emotions shown in facial expressions? |
|
Definition
We might expect that giving testosterone
to the frst person would lead to a greedy ofer, but in fact
the women receiving testosterone ofered their partner a bit
more money, on average, than did those receiving a placebo
(Eisenegger, Naef, Snozzi, Heinrichs, & Fehr, 2010). Tat
reaction doesn’t make sense in terms of aggression, although
it might make sense in terms of enhancing one’s status. Tat
is, someone who ofers the other person a good share of the
money is saying, “I’m so successful that I can aford to be
generous with you.” women received testosterone,
most became less accurate at recognizing facial expressions
of anger (van Honk & Schutter, 2007). Meanwhile, other
research shows that testosterone increases responses of the
amygdala to photos showing angry expressions (Hermans,
Ramsey, & van Honk, 2008). Evidently, testosterone afects
certain brain areas diferently, increasing the responses of
emotion-related areas, while decreasing the ability of the cere-
bral cortex to identify the emotion consciously. We can specu-
late that the result might be increased emotional arousal and
decreased ability to regulate that emotion deliberately. |
|
|
Term
| How is serotonin related to violent behavior in humans? |
|
Definition
Many studies have found low serotonin turnover in people
with a history of violent behavior, including people con-
victed of arson and other violent crimes (Virkkunen, Nuu-
tila, Goodwin, & Linnoila, 1987) and people who attempt
suicide by violent means,
Follow-up studies on people
released from prison have found that those with lower sero-
tonin turnover had a greater probability of further convictions
for violent crimes.
In the normal population, studies often fnd
a weak relationship, and sometimes a relationship in the op-
posite direction—that is, somewhat less aggression by people
with low 5-HIAA. |
|
|
Term
| How does direction of gaze of another person affect human experience of emotion? |
|
Definition
Consequently, you
recognize an angry expression faster if it is directed toward
you and a fearful expression faster if it is directed to the side .
The amygdala responds more strongly to an angry face directed
away from the viewer and to a frightened face directed toward the
viewer. |
|
|
Term
| **Damage to the human amygdala interferes with the social judgments we make about people. Describe and explainthese effects. |
|
Definition
When they examine emotional
pictures, they can classify them as pleasant vs. unpleasant
about as well as anyone else. However, they experience little
arousal from viewing unpleasant pictures (Berntson, Bechara,
Damasio, Tranel, & Cacioppo, 2007). Tat is, they continue
to experience the cognitive aspect of unpleasant emotions, but
not the feeling aspect.
M and other people with Urbach-Wiethe disease of-
ten fail to recognize the emotional expressions in faces, es-
pecially expressions of fear or disgust (Boucsein, Weniger,
Mursch, Steinhof, & Irle, 2001). Even when they recognize
an expression as fear or disgust, they rate it as less intense
than other people do, and they are less likely than average
to remember a photo of an emotional expression if they see
the same photo an hour later.
People with damage to the amygdala simply do not hold interest in other peoples eyes and therefor do not see fear or discust in others. |
|
|
Term
| Describe how (1) benzodiazepines and (2)alcohol reduces anxiety. |
|
Definition
Te most common anti-anxiety drugs (“anxiolytic drugs”)
are the benzodiazepines (BEN-zo-die-AZ-uh-peens), such
as diazepam (trade name Valium), chlordiazepoxide (Lib-
rium), and alprazolam (Xanax). Benzodiazepines bind to the
GABAA receptor, which includes a site that binds GABA as
well as sites that modify the sensitivity of the GABA site.Benzodiazepines exert their anti-anxiety efects in the
amygdala, hypothalamus, midbrain, and several other areas.
Alcohol promotes the fow of chloride ions through the
GABA A receptor complex by binding strongly at a special
site found on only certain kinds of GABA A receptors
(Glykys et al., 2007). Alcohol infuences the brain in
other ways as well, but the effects on GABA are respon-
sible for alcohol’s anti-anxiety and intoxicating effects.
Drugs that block the effects of alcohol on the GABA A
receptor complex also block most of alcohol’s behav-
ioral effects. One experimental drug, known as Ro15-
4513, is particularly effective in this regard (Suzdak et
al., 1986). Besides affecting the GABA A receptor com-
plex, Ro15-4513 blocks the effects of alcohol on motor
coordination, its depressant action on the brain, and its
ability to reduce anxiety. |
|
|
Term
| Discuss some of theeffects of stress on the immune system. |
|
Definition
Many of the symp-
toms of depression, such as loss of interest and loss of appe-
tite, are similar to those of illness and are probably related to
the increased cytokines found in depressed people (Dantzer,
O’Connor, Freund, Johnson, & Kelley, 2008). In short, if you
have been under much stress and start to feel ill, one possibil-
ity is that your symptoms are reactions to the stress itself.
A prolonged stress response is as draining on the body
as a prolonged illness would |
|
|
Term
| How does prolonged stress damage the hippocampus? |
|
Definition
Stress
releases cortisol, and cortisol enhances metabolic activity
throughout the body. When metabolic activity is high in the
hippocampus, its cells become more vulnerable. Toxins or
overstimulation are then more likely than usual to damage
or kill neurons in the hippocampus |
|
|
Term
| Discuss the relationship between PTSD and the hippocampus and cortisol. |
|
Definition
Most
PTSD victims have a smaller than average hippocampus
(Stein, Hanna, Koverola, Torchia, & McClarty, 1997). It
might seem natural to assume that severe stress elevated the
cortisol secretion and that the high cortisol levels damaged the
hippocampus. However, PTSD victims show lower than nor-
mal cortisol levels both immediately after the traumatic eventand weeks later (Delahanty, Raimonde, & Spoonster, 2000;
Yehuda, 1997). Te low levels suggest another hypothesis:
Perhaps people with low cortisol levels are ill-equipped to
combat stress and therefore more vulnerable to the damaging
efects of stress and more prone than other people to PTSD. |
|
|
Term
|
Definition
—the forebrain areas sur-
rounding the thalamus—has been regarded as critical for
emotion. |
|
|
Term
| general adaptation syndrome |
|
Definition
Selye inferred that any threat to the
body, in addition to its specifc efects, activated a general-
ized response to stress, which he called the generaladapta-
tionsyndrome. Te initial stage, which he called alarm, is
characterized by increased activity of the sympathetic ner-
vous system, readying the body for brief emergency activ-
ity. During the second stage, resistance, the sympathetic re-
sponse declines, but the adrenal cortex secretes cortisol and
other hormones that enable the body to maintain prolonged
alertness, fght infections, and heal wounds. After intense,
prolonged stress, the body enters the third stage, exhaustion.
During this stage, the individual is tired, inactive, and vul-
nerable because the nervous system and immune systems no
longer have the energy to sustain their heightened responses |
|
|
Term
|
Definition
When neurons release serotonin, they reabsorb most
of it and synthesize enough to replace the amount that washed
away. Tus, the amount present in neurons remains fairly con-
stant, and if we examine that amount, we have little idea how
much the neurons have been releasing. However, if we measure
the serotonin metabolites in body fuids, we gauge the turnover,
which is the amount that neurons released and replaced. |
|
|
