Right rolandic activation during speech perception in stutterers:a MEG study
Katja Biermann-Ruben,a,*Riitta Salmelin,b and Alfons Schnitzler a
a Department of Neurology,MEG Laboratory,University of Duesseldorf,Germany
b
Brain Research Unit,Low Temperature Laboratory,Helsinki University of Technology,Finland
Received 17May 2004;revised 9August 2004;accepted 19November 2004Available online 10February 2005
The focus of our magnetoencephalographic (MEG)study was to obtain further insight into the neuronal organization of language processing in stutterers.We recorded neuronal activity of 10male developmental stutterers and 10male controls,while they listened to pure tones,to words in order to repeat them,and to sentences in order to either repeat or transform them into passive form.Stimulation with pure tones resulted in similar activation patterns in the two groups,but differences emerged in the more complex auditory language tasks.In the stutterers,the left inferior frontal cortex was activated for a short while from 95to 145ms after sentence onset,which was not evident in the controls nor in either group during the word task.In both subject groups,the left rolandic area was activated when listening to the speech stimuli,but in the stutterers,there was an additional activation of the right rolandic area from 315ms onwards,which was more pronounced in the sentence than word task.Activation of areas typically associated with language production was thus observed also during speech perception both in controls and in stutterers.Previous research on speech production in stutterers has found abnormalities in both the amount and timing of activation in these areas.The present data suggest that activation in the left inferior frontal and right rolandic areas in stutterers differs from that in controls also during speech perception.D 2004Elsevier Inc.All rights reserved.Keywords:Stutterer;Speech;Rolandic activation
Introduction
Stuttering is primarily a motor speech disorder that affects about 1%of the population,with men being affected three to four times more often than women (Starkweather,1987).Many techniques that may improve speech performance of stutterers have been known for decades—such as external timing of speech
flow (Brady,1969),suppression or alteration of acoustic feedback of speech (Cherry et al.,1955;Natke,2000;Neelley,1961)or chorus reading (Johnson and Rosen,1937)but the neural mechanisms underlying language processing in stutterers have only been investigated with modern imaging techniques (PET,MRI,MEG)during the past 10years.
According to two PET studies,brain metabolism during rest does not differ between stutterers and controls (Braun et al.,1997;Ingham et al.,1996).During stuttering,neuronal activity is stronger in speech-motor-related brain areas than during fluent speech,particularly in the right hemisphere (Braun et al.,1997;Fox et al.,1996,2000).Furthermore,in fronto-temporal and temporo-parietal areas of the left hemisphere there is less activation during stuttering than during induced fluency and,in general,less activation in stutterers than in fluent speakers (Braun et al.,1997;Fox et al.,1996,2000;Wu et al.,1995).Finally,just prior to overt reading of single words,stutterers show an unusual time course of activation in the left inferior frontal speech planning area and left rolandic motor executive areas as compared with fluent speakers:fluent speakers first activate the inferior frontal area and thereafter rolandic areas,but in stutterers,the order is reversed (Salmelin et al.,2000).A recent MRI study using diffusion tensor imaging revealed that stutterers show structural differences in the left rolandic operculum in terms of less fiber coherence within this region,which may contribute to the observed differences in timing (Sommer et al.,2002).
The aim of the present study was to provide further information about the time course of activation during auditory language processing and speech preparation in stutterers and fluent speakers.On the basis of neuroimaging results described above we expected to detect differences between stutterers and controls in the timing or strength of activation of the left-hemisphere language-related areas and the rolandic areas.Such differences in activation were also assumed to be task dependent:we hypothesized that activation in stutterers increases when the task becomes more complex and requires more articulatory planning.Altered auditory feedback is known to enhance fluency in stutterers,suggesting that the auditory system has a modulating effect on stuttering (e.g.Cherry et al.,1955;Natke,2000;Neelley,1961).Therefore,it is likely that
1053-8119/$-see front matter D 2004Elsevier Inc.All rights reserved.*Corresponding author.Department of Neurology,MEG-Laboratory,Moorenstrasse 5,Heinrich-Heine-University,40225Duesseldorf,Germany.Fax:+492118119033.
E-mail address:K.Biermann-Ruben@uni-duesseldorf.de (K.Biermann-Ruben).
Available online on ScienceDirect
(https://www.doczj.com/doc/db11675895.html,)https://www.doczj.com/doc/db11675895.html,/locate/ynimg NeuroImage 25(2005)793–801
the expected differences in activation patterns between fluent speakers and stutterers could be evident already during the reception phase when subjects listen to speech,at least when they know that they have to speak subsequently.We are not aware of any neuroimaging data addressing this question.In the present study,we used whole-head MEG providing high spatial and temporal resolution to non-invasively monitor cortical dynamics during a simple word repetition task and a more complex sentence repetition/transformation task.
Materials and methods
Subjects
Ten male developmental stutterers(age26–40years,mean30 years)and10fluently speaking male subjects(age26–42years, mean31years)participated in our study.The control subjects had no language or speech disorders,nor did they have a family history of such disorders for at least two generations.None of the control subjects showed signs of stuttering during the entire measurement procedure.All stuttering subjects had participated in at least one therapy,but no subject was in therapy during the year immediately preceding this MEG study.Therapies varied with respect to onset (early childhood to late thirties),duration(2weeks to4years),and therapists(speech therapists,psychologists,physicians,other). Most subjects reported that they had difficulties transferring the therapeutical contents into their daily life and positive results therefore only persisted for a short while.Stuttering severity was classified as mild to moderate in three subjects,moderate to severe in three subjects and severe to very severe in four subjects according to Riley(1972).None of the subjects suffered from any other neurological or otological disease and the mother tongue was monolingually German for all.Handedness of all subjects was tested right dominant with no statistically significant difference between subject groups(Hand–Dominanz Test(Steingru¨ber,1976) Mann–Whitney U test;P=0.597,handedness questionnaire (Annett,1970)U test;P=0.823).Subjects were contacted via newspaper article and were paid for participation.They signed an informed consent.
Paradigms
Auditory cortical responses to simple nonspeech tones were determined using alternating stimulation of the left and right ear with1kHz pure tones of50ms duration and15ms rise and fall times.Loudness was individually adjusted for each ear to70dB above hearing threshold.The interstimulus interval(ISI)was randomized between800and1200ms.Auditory stimulation was performed twice,before each of the two language paradigms described below.Each ear was stimulated about150times per measurement.The simple nonspeech tones were used to evaluate basic auditory cortical processing in fluent speakers and stutterers.
Two paradigms using acoustically presented language stimuli were performed.The first was a b word-paradigm Q while the second was a more complex b sentence-paradigm Q.
In the word-paradigm,subjects heard a binaurally presented single German noun spoken by a female German speaker and digitized at44.1kHz(STIM Audio System,NEUROSCAN,INC). All of the245presented words derived from a stimulus list used in 2000).The words had two(128words),three(107),or four(10) syllables,and had a concrete(48%)or abstract(42%)meaning,or both(10%).Durations ranged from613to1132ms(mean849ms). Five hundred milliseconds after word offset,subjects heard a tone (1kHz,50ms)indicating that they now should repeat the word. The next noun was presented at a constant ISI of4.1s after tone offset.
In the sentence-paradigm,subjects heard binaurally presented sentences that consisted of three words(subject–verb–object,e.g., b doctors heal wounds Q).Sentences were spoken and digitized in the same way as words.All of the400presented sentences were different.Sentence duration ranged from1221to2595ms(mean 1854ms).The set of sentences was divided into comparable halves taking into account the distribution of sentence lengths and regularity/irregularity of verbs.Five hundred milliseconds after sentence offset subjects heard either b[we:]Q or b[pe:]Q.Those simuli prompted subjects to repeat the sentence(b[we:]Q for b wiederholen Q,i.e.,repeat)or to transform the sentence into the German passive form(b[pe:]Q for b passiv Q,i.e.,passive,for example b wounds are healed by doctors Q,which is more common in German language than in English).b[we:]Q and b[pe:]Q had a duration of450ms each and differed in sound only by the onset consonant.Both subject groups were randomly divided into halves, one half performing sentence set1with b[we:]Q and2with b[pe:]Q and vice versa.Stimulus onset asynchrony(SOA)between sentence onsets was adjusted to individual speech performance during the measurement,that is,the next sentence was presented only when the subject had completely finished repeating or transforming the previous sentence.Mean SOA was7.8s F 1.7SD for controls(range4.5–30.2s)and9.0s F4.0SD for stutterers(range5.3–103.9s).
Data acquisition and data processing
A122-channel whole-head neuromagnetometer device was used for this study(Neuromag-122k;Ahonen et al.,1993).MEG signals are associated with synchronous postsynaptic activation in tens of thousands of parallel apical dendrites of pyramidal cells (Ha¨ma¨la¨inen et al.,1993).MEG is most sensitive to electric currents flowing parallel to the skull,that is,fissural activation. Magnetic signals were digitized at397to513Hz depending on the paradigm,filtered between0.03and130Hz and continuously recorded for offline analysis.Eye movements and blinks were recorded with horizontal and vertical electrooculography(EOG) for offline artifact rejection(individually adjusted thresholds, range50to250A V).Mouth movement was measured with lip-electromyography(lip-EMG)for data analysis of the speech production phase(not reported here).Furthermore,two micro-phone signals were recorded,with one directly fed into the AD-converter and stored in the same file with the MEG signals and the other stored on a digital audio tape(TASCAM,TEAC CORPO-RATION).Continuous data was high-pass filtered at0.2Hz offline and averaged to stimulus onset(pure tones,words, sentences).
Anatomical MR images were obtained for19subjects. Coordinate systems of MRI and MEG space were aligned using a3D-digitizer(Polhemus Isotrak R)to mark anatomical landmarks that can be easily detected in anatomical MR images(nasion,right and left preauricular points)and small Head Position Indicator (HPI)coils attached to the subject’s head.The HPI coil positions
K.Biermann-Ruben et al./NeuroImage25(2005)793–801 794
The averaged data was analyzed using the equivalent current dipole source modeling technique(Ha¨ma¨la¨inen et al.,1993),as previously applied in several studies of language function(e.g., Helenius et al.,1998;Salmelin et al.,2000).Magnetic fields to pure tone stimulation were modeled by sources in each hemisphere about100ms after stimulus onset.For this purpose,20sensors covering each temporal cortex were selected and one equivalent current dipole(ECD)per hemisphere was selected that explained the field best.The source locations were kept fixed while their amplitudes were allowed to vary over time to best account for the field pattern recorded by all122sensors.Euclidean distances between the sources within each hemisphere(1st vs.2nd measure-ment)were calculated to estimate replicability of localization. Differences between groups and hemispheres were tested using a two-way ANOV A with factors group(2)and hemisphere(2).One source was then selected per hemisphere to represent the auditory cortical activation,according to goodness of fit of the source modeling procedure(N85%;mean F SEM96F0.5%).The localization of the sources on the subject’s anatomical MRI was used as an additional criterion to discard sources that were located unreasonably superficial or deep in the brain.Then,these selected source locations in the left and right auditory cortex were kept fixed,while source strengths[nAm,nanoampere-metre]were calculated over time,separately for both measurements.Peak amplitudes of the prominent N100m were taken and correlated between the two measurements to estimate replicability of activation strengths within subjects.Peak amplitudes furthermore were compared between groups for both measurements and hemispheres(ANOV A,between group factor b group Q(2),within group factors b measurement Q(2)and b hemisphere Q(2)).
For the two language paradigms,magnetic fields were averaged fromà100to1000ms with respect to word onset and sentence onset.Because stuttering did not occur in a sufficient number of trials to obtain a good signal-to-noise ratio for evoked responses, only epochs with subsequent fluent speech were taken into account.The resulting fields were modeled with equivalent current dipoles individually for each subject and task.The process of source modeling consists of a continuous interplay between visual inspection of local signal variations in the measured magnetic response(122sensors),search for dipolar field patterns and an evaluation of how well the model explains the measured field (goodness-of-fit).Neuromagnetic activity is modeled at the times when each dipolar pattern is clearest;for the estimation of a dipole, only those sensors are selected that cover the active area(usually 12to20sensors).A dipole’s location and orientation represent the center of gravity of the active cortical patch and the direction of current flow within this area,respectively.The amplitude of a dipole[nAm]represents the magnitude of cortical activity.The current dipoles were identified one by one in a time interval from0 to1000ms.The goodness-of-fit value ranged between73%and 99%across subjects and analysis intervals.
The complete set of sources was brought into a multi-dipole model where the dipole locations and orientations were kept fixed while the amplitudes were allowed to vary to best explain the measured MEG signals.To be evaluated as active and to be included in the further analysis,a dipole’s maximum amplitude had to exceed three standard deviations of its prestimulus base level activation(à100to0ms with respect to word/sentence onset), which corresponds to a probability of approximately99.8%.
The resulting sources for word reception and sentence reception subject to make the tasks comparable with respect to source strengths and latencies.When a specific source area(dipole location and orientation)was found to be active in both tasks,we opted for the dipole that was appropriate for both conditions.Guiding criteria were again goodness of fit(%)and resulting interaction with other sources of the model.Interaction was measured as the angle between any pair of dipoles and was not smaller than308.In case a source was calculated only for one language task,we selected it for the combined model.This final receptive model was then applied to both the word and sentence data to determine the time courses of activation in the different source areas.
The sources of the receptive model were displayed on the individual subjects’brains.According to anatomical landmarks, that is,sylvian fissure,central sulcus,and bordering gyri,sources of all subjects were then transferred to one representative brain.
Regions of interest(ROIs)
Sources were clustered interindividually according to anatom-ical criteria as well as source orientation and time course of activation to represent comparable activation in different subjects.
A cluster was only used for further analysis if it contained sources from at least five stutterers or five controls.If a subject did not have a source in a defined cluster,the activation was set equal to zero nAm,representing the assumption that the activation was too small to be detected.If one subject had two sources within one cluster,the time courses of these activations were added together. For each cluster,activations were averaged separately for fluent speakers and stutterers for word reception and sentence reception. Time windows of interest(TOIs)
Because activations evolved rather slowly,we did not calculate peak amplitudes for statistical comparisons between conditions and groups,but defined time windows of interest(TOIs;Salmelin et al., 2000).Time-locked responses are typically quite sharp within the first few hundred ms after stimulus onset and become temporally more widespread or sustained at longer latencies.Therefore,in each ROI,we searched for time windows where the mean source strengths plus/minus the standard errors of mean(SEM)in stutterers and fluent speakers did not overlap for at least50ms up to latencies of400ms,or for at least100ms at latencies beyond 400ms.This comparison was done separately for the word and sentence tasks.If one TOI was found for only one task,it was also applied for the other task.Within a defined TOI,mean amplitudes were calculated for each subject and task.
Statistical evaluation
Mean amplitudes within certain ROI/TOIs were compared between groups for each ROI/TOI using two-way ANOV A with group(controls,stutterers)as between group factor and task(word, sentence)as within group factor.
Results
Pure tone stimulation
Auditory responses to simple1kHz tones were obtained in nine
K.Biermann-Ruben et al./NeuroImage25(2005)793–801795
sources of activation were located in the superior temporal cortex within Heschl’s gyrus or Planum temporale.The source areas were very similar in the two recordings:in the control group,the Euclidean distance between the corresponding sources was 4.5F 0.8mm (mean F SEM)in the right hemisphere and 6.2F 0.7mm in the left hemisphere.For the stutterers,the distance was 7.8F 2.2mm in the right hemisphere and 5.8F 1.8mm in the left hemisphere.There were no significant differences by hemisphere or subject group.
Peak amplitudes of the activations to contralateral stimulation did not differ between the two recordings as indicated by a high correlation of 0.96for the right hemisphere sources and 0.95for the left hemisphere sources.Peak amplitudes of stutterers and controls (Table 1)did not differ by group or recording session.Auditory processing up to 100ms as probed by tonal stimulation should thus be comparable in the two subject groups.Auditory word and sentence presentation
Stutterers performed both tasks almost fluently.Only three subjects stuttered occasionally in the word task (1,12,and 90times).Six subjects stuttered in the sentence task (1to 127times depending on the condition);stuttering occurred more frequently in sentence transformation than repetition (cumulative sum of stuttered trials 266versus 102).Because of insufficient number of stutter events,only fluent epochs were included in the further analysis.
Fig.1shows whole-head MEG recordings during word and sentence perception (overlaid)in one representative control subject.The signals are strongest over the temporal areas,with a sharp peak of activation at about 100ms,followed by more sustained activity.
MEG data averaged with respect to the onset of word and sentence presentation was analyzed using source modeling procedure as described in Materials and methods.One b reception-model Q was obtained for each subject (5–8sources per subject,mean 6.6).Regions of interest (ROIs)
The sources were transferred to one representative brain and they clustered in four main areas in each hemisphere (Fig.2).According to location,direction of current flow,and time course of the sources,we defined a superior-temporal cluster (I,II),a temporo-parietal cluster (III,IV),an inferior-frontal cluster (V ,VI),and a rolandic cluster (VII,VIII).The superior-temporal cluster mainly covers Heschl’s gyrus and Planum temporale,with current flow in the superior-to-inferior direction.The temporo-parietal area
was defined as the area surrounding the posterior part of the Sylvian fissure containing gyrus supramarginalis,gyrus angularis,and gyrus temporalis superior pars posterior.Here,current flow was typically in the posterior-to-anterior direction.The inferior-frontal area was limited by the central sulcus,the inferior frontal sulcus and the anterior ascending part of the Sylvian fissure.The rolandic area mainly contains the precentral but also to some extent the postcentral gyrus,being laterally bordered by the inferior frontal gyrus.Sometimes dipolar sources exceeded the structural borders defining a cluster but had a typical direction of current flow of the sources within that cluster.Direction of current flow was therefore taken as a functional criterion supplementing anatomical criteria for the definition of a cluster.The number of controls and stutterers who had sources in the defined clusters is given in Fig.2.We also found other sources,located outside of these clear clusters,in total 10sources in the left hemisphere and eight sources in the right hemisphere (nine sources from the control group,nine sources from the stutterers).These sources were scattered over various brain areas in a rather unsystematic manner and they were not included in the further analysis.
Group mean activation strengths of clustered sources are overlaid for both groups for word and sentence task and separately for all ROIs in Fig.3.There was a transient bilateral activation of the superior-temporal area at about 100ms that was followed by a sustained activation,predominantly in the left hemisphere,which reached the maximum between 400and 600ms.At 200–400ms,bilateral temporo-parietal and inferior-frontal activity was detected in 8–14subjects depending on cluster and hemisphere (details concerning the number of subjects are given in Fig.2).In controls,rolandic activity peaked at about 200ms bilaterally followed by a sustained signal in the left hemisphere up to 1000ms and a rapid decrease in the right hemisphere.In stutterers,left rolandic activity was delayed (word task)with respect to that in controls by about 100ms (see below for evaluation of time windows of interest,TOIs).Furthermore,the right rolandic area showed a persistent activation up to 800ms in the word task and up to 1000ms in the sentence task.The pattern of activation was comparable for word and sentence processing.Time windows of interest (TOIs)
We identified five time ranges (in five ROIs)where activation patterns potentially differed between the stutterer and control groups (arrowheads in Fig.3).Three of these time windows of interest (TOIs)stem from comparisons of activation in the sentence task,two result from comparisons within the word task.The TOIs,ROIs,group means,and P values revealed by analyses of variance are given in Table 2,and the results are illustrated in Fig.4.
Significant group differences emerged in the left inferior frontal area at 95–145ms and in the right rolandic area at 315–1000ms.In these ROI/TOIs,stutterers had stronger activations than control subjects.Activation of the left inferior frontal ROI at 95–145ms also showed a significant task effect,with clear activation in the sentence task but essentially no signal in the word task.This effect is predominantly caused by the stutterers,as confirmed by post hoc tests of simple effects (planned comparisons;controls:sentence N word,P N 0.50;stutterers:sentence N word,P b 0.01).Furthermore,analysis revealed significant group-by-task interac-tions in the right temporo-parietal ROI at 330–390ms and the left rolandic ROI at 235–330ms.Both interactions resulted from Table 1
N100m amplitudes to tone stimulation Measurement Left hemisphere mean (SD)Right hemisphere mean (SD)Controls 1st 43.9(15.7)51.3(21.7)2nd 46.6(13.3)51.1(23.9)Stutterers
1st 43.2(27.0)61.5(31.4)2nd
45.2
(26.2)
68.3
(29.2)
Mean peak amplitudes and SD [nAm]of the N100m in both hemispheres for controls and stutterers in the first and second measurements of tone K.Biermann-Ruben et al./NeuroImage 25(2005)793–801
796
Fig.1.MEG signals measured with 122sensors for one representative control subject in the word and sentence tasks.The sensor array is viewed from above with the subject’s right ear on the right and left ear on the left.Vertical lines indicate word/sentence
onset.
Fig.2.Individual sources for word and sentence reception transferred to one representative brain.Sources of stutterers (white squares)and controls (black circles)clustered within four areas in each hemisphere.The black bars indicate typical directions of current flow in each cluster.The amount of subjects who had at least one source in the respective cluster is given in the table below.The number of subjects with more than one source in the cluster is given in K.Biermann-Ruben et al./NeuroImage 25(2005)793–801797
with the word task,while in stutterers,the activations increased from word to sentence task.Post hoc planned comparisons revealed no significant differences between groups when each task was tested separately,either in the right temporo-parietal or in the left rolandic area.These results therefore will not be discussed in detail.
Discussion
Auditory processing up to 100ms was probed by tonal stimulation,which was performed before both the word and the sentence task.The locations of activated areas and activation
strengths were indistinguishable between the two recordings.No group differences were found between the fluent speakers and stutterers.Differences in the language tasks therefore cannot be directly attributed to basic auditory processing per se.
For the language tasks sources of both subject groups mainly clustered in four areas typically referred to as areas of auditory processing (superior-temporal area),language reception (temporo-parietal area),speech preparation (inferior-frontal area),and sensorimotor processing (rolandic area)(for a review of the neuroimaging literature,see Cabeza and Nyberg,2000).
For the auditory word task,we used the same words that were used previously in an overt word reading task comparing stutterers and controls (Salmelin et al.,2000).Interestingly,many of
the
Fig.3.Mean activation strengths [nAm]of clustered sources of stutterers (grey)and controls (black)overlayed for word (left columns)and sentence task (right columns).Left hemisphere activation is plotted in the first and third columns,right hemisphere activation in the second and fourth columns.Time scales refer to word and sentence onsets.Black arrowheads indicate time windows of interest (TOIs,see text).
Table 2
Activations in the language tasks:comparisons between groups TOI [ms]ROI Task Mean (SD)controls [nAm]Mean (SD)stutterers [nAm]Effects (ANOV A)Group Task Interaction 690–1000left
word 12.9(7.3)12.6(9.7)n.s.n.s.n.s.sup.-temporal sentence 13.0(8.2) 6.7(7.6)330–390right
word 6.4(9.8)0.8(5.5)n.s.n.s.P b 0.021temp.-parietal sentence 2.7(6.6) 5.1(8.9)95–145left
word à0.9(3.8) 1.1(4.6)P b 0.020P b 0.021n.s.inf.-frontal sentence 0.2(3.0) 5.8(5.0)235–330left word 6.9(9.0) 1.0(7.0)n.s.n.s.P b 0.032rolandic sentence 4.0(5.0) 2.7(7.2)315–1000
right word 0.3(5.2) 3.0(4.5)P b 0.024
n.s.
n.s.
rolandic
sentence
0.3
(1.1)
3.8
(3.8)
Time windows of interest (TOIs)for regions of interest (ROIs)and mean activations within these ROI/TOIs for controls and stutterers during word and sentence reception.P values of main effects and interactions revealed by analyses of variance (group (2)?task (2))for each ROI/TOI are given in columns on K.Biermann-Ruben et al./NeuroImage 25(2005)793–801
798
relevant source clusters in Salmelin et al.were rather similar to those found in the present study using auditory stimuli.The superior-temporal response around400to600ms was found bilaterally in the auditory task reported here but predominantly in the left hemisphere in the visual task reported by Salmelin et al. (2000).These observations are in agreement with previous MEG reports of bilateral temporal activation in speech comprehension (Helenius et al.,2002)but left-lateralized activation in reading comprehension(Helenius et al.,1998).Furthermore,the visual task resulted in activation of occipital areas,which was not present in the auditory task.The early modality-specific and later supramodal activation patterns are in line with recent reports on direct comparison of visual and auditory word processing(Booth et al., 2002;Marinkovic et al.,2003).
Of previous time-sensitive neuroimaging studies,the one that comes closest to the present experimental design is that on auditory word and sentence comprehension by Helenius et al.(2002).The authors compared responses to semantically appropriate and inappropriate sentence-ending words.Activation concentrated to the superior temporal cortex bilaterally,with a typical relatively non-specific auditory activation at100ms and a subsequent sustained activation at200–600ms,reflecting semantic processing (usually referred to as the N400response;Kutas and Hillyard, 1984).In that study,the subjects only listened to the stimuli.
In the present study,the subjects were additionally required to prepare for articulation after the stimulus presentation.Indeed,we found a comparable type of bilateral superior-temporal activation, peaking at100ms and400to600ms,as Helenius et al.(2002) but there was clear-cut activation also in other brain regions, namely in the temporo-parietal and inferior-frontal areas at200–400ms and in the rolandic areas peaking at200ms and persisting in the left and right(stutterers)rolandic area at least up to800ms. In both subject groups and all regions of interest,activity could be determined in both hemispheres,pointing to a role of the right hemisphere in word and sentence processing and speech preparation.
As in word reading(Salmelin et al.,2000),group differences in and rolandic areas.In the left inferior frontal area,at95to145ms, stutterers showed enlarged activation as compared with controls when processing sentences.Some imaging studies have reported activation of left inferior-frontal area in subvocal or overt word repetition(Hinke et al.,1993;Price et al.,1996)or in auditory sentence comprehension(Schlosser et al.,1998).This area comprising inferior parts of the primary motor cortex(probably face/mouth area)and ventral premotor regions(Broca’s area, Brodmann’s area(BA)44)as well as frontal opercular regions is necessary for articulatory planning of speech as well as for executive motor functions(Dronkers,1996;Penfield and Roberts, 1959).Moreover,the inferior-frontal region also appears to be involved in functions of speech reception and phonetic analysis (Fiez et al.,1995;Price et al.,1996;Zatorre et al.,1992).
Since word and sentence tasks both started with auditory presentation of a noun which obviously lasted longer than the time window under consideration(95–145ms),it is unlikely that the differences could be due to the stimulus material.Furthermore, those differences should then have affected both groups.Stuttering is more likely to occur with production of sentences than single words and,interestingly,it then occurs at the beginning of the sentence(Quarrington,1965).In our sentence task subjects had to transform the sentences with a probability of50%to the passive form,which they did not know before presentation of the auditory cue(b[we:]Q or b[pe:]Q).Enlarged load of linguistic and phono-logical planning typically results in higher amount of stuttering (Brown and Moren,1942;Lanyon and Duprez,1970;Soderberg, 1966).Interestingly,anticipation has a crucial influence on speech performance:a short sentence is stuttered more often if it is the first part of a long sentence than if it is the last part or if it stands alone (Jayaram,1984;Tornick and Bloodstein,1976).We interpret the obtained group difference in the left inferior frontal region in terms of anticipation of enlarged load of articulatory planning in stutterers dealing with sentences.Whether the exceptionally strong activation in stutterers is characteristic to their general linguistic-motor organization(also during fluent speech)or whether this increased activation might in fact prevent them from stuttering
Fig.4.Mean activation strengths[nAm]for ROI/TOIs(separate columns),tasks(word:left,sentence:right)and subjects(controls:black;stutterers:grey);only significant results of comparisons are shown.Effects(group,task,group-by-task interaction)are listed at the top of each box(for P values please see Table2).
K.Biermann-Ruben et al./NeuroImage25(2005)793–801799
for articulatory planning was anticipated in the word task and, indeed,even stutterers had activity close to zero within this early time window in the left inferior-frontal area.
The observed interactions in the left rolandic area at235to330 ms and in the right temporo-parietal area at330to390ms may also be interpreted as task effects specific to stutterers:they show enlarged activation in the sentence task with respect to the word task,whereas this pattern is reversed in controls.It seems that many areas become more active in stutterers when task complexity and,therefore,the tendency toward stuttering increases.That for controls activation in these areas is smaller than in the word task may be caused by the sequence of measurements:the word task always preceded the sentence task and control subjects may have become used to the experimental procedure.
Another difference between groups was detected at315–1000 ms in the right rolandic area,again in the more complex sentence task.Whereas stutterers activated the right rolandic cortex at that time,controls showed essentially no activity there in this time window.In contrast,during actual word production,Salmelin et al. (2000)reported a pronounced activation of the right rolandic area in control subjects but an abnormally weak activation in the stutterers,as measured by the evoked responses.
Exceptionally strong activation of the right hemisphere in stutterers has been indicated in several PET studies(Braun et al., 1997;Fox et al.,1996,2000;Wu et al.,1995).Because of the low temporal resolution of PET and the paradigms used(reading alone, chorus reading,narrative,paced,or overlearned speech)no information could be derived about the time frame of the increased activity.The present data suggest that right hemisphere rolandic activation of stutterers is abnormally enhanced when they listen to speech,before articulation.We interpret the left rolandic activation in controls and the additional involvement of the right rolandic area in stutterers as one piece of evidence for an altered cerebral dominance in stutterers,which becomes obvious in speech perception,well before overt speech production,and which may correlate with task complexity.The cerebral dominance theory of stuttering is very old,claiming that unusually weak left hemisphere lateralization of the b speech Q function results in hemispheric rivalry during speech production,which causes stuttering(Travis,1927). This explanation is obviously far too simple;the right hemisphere is strongly involved in speech perception and production also in fluent speakers.Present knowledge suggests that several inter-connected bihemispheric cortical(and of course subcortical)areas are recruited in successful language performance.Nevertheless,as the general concept of lateralization accounts for handedness,it may also be applicable in characterizing the final stage of speech production,articulatory output.In this framework,the group differences in activation of the sensorimotor(rolandic)area may be interpreted in terms of weaker left hemisphere lateralization of speech sensorimotor functions in stutterers.The strength of rolandic activation in stutterers did not correlate with stuttering severity and,unfortunately,there were too few stuttered trials to allow direct evaluation of activation preceding stuttered versus fluent production.Therefore,interpretation of the unusually strong right rolandic activation in stutterers remains speculative at this point.
In conclusion,we showed that there are differences in the time course of neurophysiological signals between stutterers and fluent speakers during auditory reception,well before the overt spoken response.These differences are detected even when the stutterers inferior-frontal cortex and later sustained activation of the right rolandic cortex did not correlate with the severity of stuttering. Direct comparison of the cortical dynamics of stuttered and fluent speech production in the same individuals could be best achieved in natural,continuous language tasks.Such experiments are now becoming feasible with the advent of analysis tools for time-sensitive cortico-cortical coherence(Gross et al.,2001). Acknowledgments
This study was supported by the Human Frontier Science Program and the Academy of Finland.We thank Dr.Joachim Gross for helpful discussions especially during data analysis,Dr. Ulrich Natke for expert advice during the early phase of this project,and Frank Schmitz and Erika Raedisch for technical help.
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读《写给未来的你》有感 偶然间从收音机里听了余光中先生的一首诗《写给未来的你》。听了一遍，还想听。于是，一遍，两遍......... 那字里行间充满着的真情，在播音员沙哑而又有磁性的声音中流露。 这首诗，是长者对晚辈的忠告；这首诗，是智者对所有人的劝诫；这首诗，是作者数十年来人生路的经验总结；这首诗，是余老先生对无数后代的寄托与期望；这首诗，更是一个有思想的人的教育箴言。 不信，自己来读一读。 写给未来的你 孩子，我希望你自始至终都是一个理想主义者。你可以是农民，可以是工程师，可以是演员，可以是流浪汉，但你必须是个理想主义者。童年，我们讲英雄故事给你听，并不是一定要你成为英雄，而是希望你具有纯正的品格。少年，我们让你接触诗歌、绘画、音乐，是为了让你的心灵填满高尚的情趣。这些高尚的情趣会支撑你的一生，使你在最严酷的冬天也不会忘记玫瑰的芳香。理想会使人出众。孩子，不要为自己的外形担忧。理想纯洁你的气质，而最美貌的女人也会因为庸俗而令人生厌。通向理想的途径往往不尽如人意，而你亦会为此受尽磨难。但是，孩子，你尽管去争取，理想主义者的结局悲壮而绝不可怜。在貌似坎坷的人生里，你会结识许多智者和君子，你会见到许多旁人无法遇到的风景和奇迹。选择平庸虽然稳妥，但绝无色彩。不要为蝇头小利放弃自己的理想，不要为某种潮
流而改换自己的信念。物质世界的外表太过复杂，你要懂得如何去拒绝虚荣的诱惑。理想不是实惠的东西，它往往不能带给你尘世的享受。因此你必须习惯无人欣赏，学会精神享受，学会与他人不同。其次，孩子，我希望你是个踏实的人。人生太过短促，而虚的东西又太多，你很容易眼花缭乱，最终一事无成。如果你是个美貌的女孩，年轻的时候会有许多男性宠你，你得到的东西太过容易，这会使你流于浅薄和虚浮；如果你是个极聪明的男孩，又会以为自己能够成就许多大事而流于轻佻。记住，每个人的能力有限，我们活在世上能做好一件事足矣。写好一本书，做好一个主妇。不要轻视平凡的人，不要投机取巧，不要攻击自己做不到的事。你长大后会知道，做好一件事太难，但绝不要放弃。你要懂得和珍惜感情。不管男人女人，不管墙内墙外，相交一场实在不易。交友的过程会有误会和摩擦，但想一想，诺大世界，有缘结伴而行的能有几人？你要明白朋友终会离去，生活中能有人伴在身边，听你倾谈，倾谈给你听，就应该感激。要爱自己和爱他人，要懂自己和懂他人。你的心要如溪水般柔软，你的眼波要像春天般明媚。你要会流泪，会孤身一人坐在黑暗中听伤感的音乐。你要懂得欣赏悲剧，悲剧能丰富你的心灵。希望你不要媚俗。你是个独立的人，无人能抹杀你的独立性，除非你向世俗妥协。要学会欣赏真，要在重重面具下看到真。世上圆滑标准的人很多，但出类拔萃的人极少。而往往出类拔萃又隐藏在卑琐狂荡之下。在形式上我们无法与既定的世俗争斗，而在内心我们都是自己的国王。如果你的脸上出现谄媚的笑容，我将会羞愧地掩面
期末检测题 时间：60分钟分值：100分 一、单项选择题（每小题2分，共20小题，40分） 1.毛泽东在《贺新郎?读史》中吟道：“人猿相揖别。只几个石头磨过，小儿时节。”对“人猿相揖别。只几个石头磨过”理解最为准确的是（） A.人与猿只在一起磨过几个石头后就告别了 B.人和猿在几个磨过的石头边告别了 C.人和动物的根本区别在于是否会制造工具 D.人和动物的根本区别在于是否会磨几个石头 2.小明来到周口店龙骨山，他可以了解到生活在距今约的北京人（） A.80万~30万年 B.70万~30万年 C.70万~20万年 D.80万~20万年 3.右图是某同学在旅游时拍摄的。图中所涉及历史人物的 主要事迹不包括（） A.建立我国第一个王朝 B.因治水有功，舜年老时推举他做了部落联盟首领 C.为治理洪水，三过家门而不入 D.通过禅让制推举启为继承者 4.下面代表了商朝青铜器典型风格的巨鼎是（） A.司母戊鼎 B.青铜立人 C.青铜神树 D.四羊方尊 5.“齐桓公对内整顿朝政，对外‘尊王攘夷’，终于九合诸侯，一匡天下，成就了春秋五霸之首的伟业。”辅佐他成就“五霸之首伟业”的人是（） A.伊尹 B.姜尚 C.管仲 D.勾践 6.春秋战国时期的土地利用率和农作物产量有了显著提高，这主要是因为（） A.农业重视使用肥料 B.青铜器在农业生产中的广泛应用 C.水利工程的兴修 D.铁农具和牛耕的推广 7.“兴，百姓苦；亡，百姓苦。”兴亡之间，战乱不断。在战乱之中，中国涌现出许多杰出的军事家，即便是他们，也把“不战而屈人之兵”作为最高的追求。被称为我国兵家鼻祖的人是（） A.孔子 B.孙膑 C.韩非 D.孙武 8.关于陈胜吴广起义，下列说法有误的是（） A.曾在陈建立政权 B.推翻了秦朝 C.在大泽乡起义 D.是中国历史上的第一次农民大起义 9.近几十年来，我国新疆地区陆续出土了许多汉代的丝织品，这主要反映了（） A.西汉时这一地区才开始出现丝织品 B.丝绸之路开通后，新疆地区与中原地区交往日益密切 C.西汉的丝织品质优价廉 D.汉代新疆人主要穿丝绸衣服 10.史书记载，某事件发生后，“边城晏闭，牛马布野，三世亡（无）犬吠之警，黎庶亡（无）干戈之役”。“某事件”指的是（） A.霍去病反击匈奴 B.昭君出塞
余光中：写给未来的孩子的信 孩子，我希望你自始至终都是一个理想主义者。 你可以是农民，可以是工程师，可以是演员，可以是流浪汉，但你必须是个理想主义者。 童年，我们讲英雄故事给你听，并不是一定要你成为英雄，而是希望你具有纯正的品格。 少年，我们让你接触诗歌、绘画、音乐，是为了让你的心灵填满高尚的情趣。 这些高尚的情趣会支撑你的一生，使你在最严酷的冬天也不会忘记玫瑰的芳香。 理想会使人出众。 孩子，不要为自己的外形担忧。 理想纯洁你的气质，而最美貌的女人也会因为庸俗而令人生厌。 通向理想的途径往往不尽如人意，而你亦会为此受尽磨难。 但是，孩子，你尽管去争取，理想主义者的结局悲壮而绝不可怜。 在貌似坎坷的人生里，你会结识许多智者和君子，你会见到许多旁人无法遇到的风景和奇迹。 选择平庸虽然稳妥，但绝无色彩。 不要为蝇头小利放弃自己的理想，不要为某种潮流而改换自己的信念。 物质世界的外表太过复杂，你要懂得如何去拒绝虚荣的诱惑。 理想不是实惠的东西，它往往不能带给你尘世的享受。
因此你必须习惯无人欣赏，学会精神享受，学会与他人不同。 其次，孩子，我希望你是个踏实的人。 人生太过短促，而虚的东西又太多，你很容易眼花缭乱，最终一事无成。 如果你是个美貌的女孩，年轻的时候会有许多男性宠你，你得到的东西太过容易，这会使你流于浅薄和虚浮； 如果你是个极聪明的男孩，又会以为自己能够成就许多大事而流于轻佻。 记住，每个人的能力有限，我们活在世上能做好一件事足矣。 写好一本书，做好一个主妇。 不要轻视平凡的人，不要投机取巧，不要攻击自己做不到的事。 你长大后会知道，做好一件事太难，但绝不要放弃。 你要懂得和珍惜感情。 不管男人女人，不管墙内墙外，相交一场实在不易。 交友的过程会有误会和摩擦，但想一想，诺大世界，有缘结伴而行的能有几人？ 你要明白朋友终会离去，生活中能有人伴在身边，听你倾谈，倾谈给你听，就应该感激。 要爱自己和爱他人，要懂自己和懂他人。 你的心要如溪水般柔软，你的眼波要像春天般明媚。 你要会流泪，会孤身一人坐在黑暗中听伤感的音乐。 你要懂得欣赏悲剧，悲剧能丰富你的心灵。 希望你不要媚俗。 你是个独立的人，无人能抹杀你的独立性，除非你向世俗妥协。 要学会欣赏真，要在重重面具下看到真。
写给未来的你830字 余光中 孩子，我希望你自始至终都是一个理想主义者，理想会使人出众，理想纯洁你的气质。通向理想的途径往往不尽如人意，而你亦会为此受尽磨难。但是，孩子，你尽管去争取，理想主义者的结局悲壮而绝不可怜。在貌似坎坷的人生里，你会结识许多智者和君子，你会见到许多旁人无法遇到的风景和奇迹。选择平庸虽然稳妥，但绝无色彩。 不要为蝇头小利放弃自己的理想，不要为某种潮流而改换自己的信念。物质世界的外表太过复杂，你要懂得如何去拒绝虚荣的诱惑。理想不是实惠的东西，它往往不能带给你尘世的享受。因此你必须习惯无人欣赏，学会精神享受，学会与他人不同。 其次，孩子，我希望你是个踏实的人。 记住，每个人的能力有限，我们活在世上能做好一件事足矣。 不要轻视平凡的人，不要投机取巧，不要攻击自己做不到的事。 你长大后会知道，做好一件事太难，但绝不要放弃。 你要懂得和珍惜感情。你要明白朋友终会离去，生活中能有人伴在身边，听你倾谈，倾谈给你听，就应该感激。要爱自己和爱他人，要懂自己和懂他人。 你的心要如溪水般柔软，你的眼波要像春天般明媚。 你要会流泪，会孤身一人坐在黑暗中听伤感的音乐。 你要懂得欣赏悲剧，悲剧能丰富你的心灵。 希望你不要媚俗。你是个独立的人，无人能抹杀你的独立性，除非你向世俗妥协。 要学会欣赏真，要在重重面具下看到真。 世上圆滑标准的人很多，但出类拔萃的人极少。而往往出类拔萃又隐藏在卑琐狂荡之下。 在形式上我们无法与既定的世俗争斗，而在内心我们都是自己的国王。 世俗的许多东西虽耀眼却无价值，不要把自己置于大众的天平上，不然你会因此无所适从，人云亦云。 孩子，还有一件事，虽然做起来很难，但相当重要，这就是要有勇气正视自己的缺点。 你会一年年地长大，会渐渐遇到比你强、比你优秀的人，会发现自己身上有许多你所厌恶的缺点。这会使你沮丧和自卑。 但你一定要正视它，不要躲避，要一点点地加以改正。战胜自己比征服他人还要艰巨和有意义。 不管世界潮流如何变化，但人的优秀品质却是永恒的：正直、勇敢、独立。 我希望你是一个优秀的人。 （原文有删改）
配套中学教材全解工具版 九年级物理上 It was last revised on January 2, 2021
第十三、十四章中考典题补充 1.（2015天津中考）图1为四冲程汽油机工作过程中的某 图1 冲程示意图，该冲程为（） A.吸气冲程 B.压缩冲程 C.做功冲程 D.排气冲程 解析：由图知，两个气门都关闭，火花塞产生电火花，活塞向下运动，因此是做功冲程，故Ｃ选项正确。 答案：C 2. (2015山东泰安中考)四冲程内燃机工作时，哪个冲程将机械能转化为内能( ) A.压缩冲程 B.做功冲程 C.吸气冲程 D.排气冲程 解析：内燃机是将内能转化为机械能的机器，它的一个工作循环包括：吸气、压缩、做功、排气四个冲程，其中压缩冲程是将机械能转化为内能；做功冲程是将内能转化为机械能，故A选项正确。 答案：A 3. (2015?湖北宜昌中考)为节约能源，需要提高热机的效率，下列措施中不能提高热 机效率的是( ) A.尽量使燃料充分燃烧 B.尽量减少热机部件间的摩擦 C.尽量减少废气带走的热量 D.尽量增加热机的工作时间
解析：提高热机效率具有重要的经济效益和社会效益，在物理学中，提高热机效率就是增加有用功或减少额外功。在热机中，使燃料充分燃烧可以提高热机效率；减少废气带走的热量可以提高热机效率；减少热机部件间的摩擦也可以提高热机效率；增加热机的工作时间不能提高热机效率。 答案：D 4. (2013四川自贡中考)如图2所示流程是用来说明单缸四冲程汽油机的一个工作循 环及涉及的主要能量转化情况。对图中①②③④的补充正确的是( ) 图2 A.①做功冲程②内能转化为机械能③压缩冲程④机械能转化为内能 B.①压缩冲程②内能转化为机械能③做功冲程④机械能转化为内能 C.①压缩冲程②机械能转化为内能③做功冲程④内能转化为机械能 D.①做功冲程②机械能转化为内能③压缩冲程④内能转化为机械能 解析：压缩冲程中，活塞压缩汽缸内的气体，使气体内能增大，将机械能转化为内能；做功冲程中，燃料燃烧产生高温高压的燃气推动活塞运动，将内能转化为机械能。所以C选项正确。 答案：C 5. (2013山东济宁中考)我国研制的“神舟九号”试验飞船在返回地面通过大气层的飞 行中，下列说法中不正确的是( ) A.飞船的机械能保持不变 B.飞船的一部分机械能转化为内能 C.飞船的重力势能越来越小 D.飞船的外表温度会升高
写给未来得您余光中 孩子我希望您自始至终都就是一个理想主义者您可以就是农民也可以就是演员可以就是工程师可以就是流浪汉但您必须就是个理想主义者童年我们讲英雄故事给您听并不就是一泄要您成为英雄而就是希望您具有纯正得品格少年我们让您接触诗歌、绘画、音乐就是为了让您得心灵填满高尚得情趣这些高尚得情趣会支撑您得一生使您在最严酷得冬天也不会忘记玫瑰得芳香理想会使人出众孩子 不要为自己得外形担忧理想纯洁您得气质而最美貌得女人也会因为庸俗而令人生厌通向理想得途径往往不尽如人意而您亦会为此受尽磨难但就是，孩子您尽管去争取理想主义者得结局悲壮而绝不可怜在貌似坎坷得人生里您会结识许多智者与君子您会见到许多旁人无法遇到得风景与奇迹选择平庸虽然稳妥但绝无色彩不要为蝇头小利放弃自己得理想不要为某种潮流而改换自己得信念物质世界得外表太过复杂您要懂得如何去拒绝虚荣得诱惑理想不就是实惠得东西它往往不能带给您尘世得享受因此您必须习惯无人欣赏 学会精神享受学会与她人不同其次，孩子 我希望您就是个踏实得人人生太过短促而虚得东四又太多您很容易眼花缭乱最终一事无成 如果您就是个美貌得女孩年轻得时候会有许多男性宠您您得到得东西太过容易这会使您流于注薄与虚浮如果您就是个极聪明得男孩又会以为自己能够成就许多大事而流于轻佻记住，每个人得能力有限我们活在世上能做好一件事足矣写好一本书做好一个主妇 不要轻视平凡得人不要投机取巧 不要攻击自己做不到得事您长大后会知道做好一件事太难但绝不要放弃您要僮得与珍惜感情不管男人女人不管墙内墙外相交一场实在不易交友得过程会有误会与摩擦但想一想诺大世界
有缘结伴而行得能有几人？您要明白朋友终会离去生活中能有人伴在身边听您倾谈，倾谈给您听，就应该感激要爱自己与爱她人 要懂自己与懂她人您得心要如溪水般柔软您得眼波要像春天般明媚您要会流泪会孤身一人坐在黑暗中听伤感得音乐您要懂得欣赏悲剧 悲剧能丰富您得心灵 希望您不要媚俗您就是个独立得人无人能抹杀您得独立性除非您向世俗妥协要学会欣赏真 要在重重而具下瞧到真世上圆滑标准得人很多但出类拔萃得人极少而往往岀类拔萃又隐藏在卑琐狂荡之下在形式上我们无法与既泄得世俗争斗而在内心我们都就是自己得国王如果您得脸上出现谄媚得笑容我将会羞愧地掩而而去 世俗得许多东西虽耀眼却无价值不要把自己宜于大众得天平上不然您会因此无所适从人云亦云在具体得做人上 我希望您不要打断别人得谈话不要娇气十足 您每天至少要拿岀两小时来读书要回信写信给您得朋友 不要老就是想着别人应该为您做些什么而要想着怎么去帮助她人借她人得东西要还 不要随便接受別人得恩惠要记住，别人得东西再好也就是别人得自己得东西再差也就是自己得孩子还有一件事 虽然做起来很难，但相当重要这就就是要有勇气正视自己得缺点您会一年年地长大会渐渐遇到比您强 比您优秀得人 会发现自己身上有许多 您所厌恶得缺点这会使您沮丧与自卑但您一左要正视它不要躲避要一点点地加以改正 战胜自己比征服她人 还要艰巨与有意义 不管世界潮流如何变化 但人得优秀品质却就是永恒得: 正直、勇敢、独立
Module 5 Cartoons 检测题 (时间：60分钟；满分：100分) 一、听力部分（15分） （一）听句子，选择正确的答语。（每个句子读一遍） 1.A.Yes, I do. B.Yes, I can. C.Not yet, but I am going to see it next Sunday. 2.A.Sorry, sir, I won’t. B.Yes, I will. C.Yes, I won’t. 3.A.In the classroom. B.With my friends. C.Five years ago. 4.A.Congratulations! B.Sorry to hear that. C.See you later. 5.A.He came two weeks ago. B.Very well. We are both football fans. C.He works very hard. （二）听对话，判断正（T）误（F）。（对话读两遍） 6.Ted has been to America twice. 7. Ted has never been to America. 8.Ted thinks Hollywood is the best place to visit. 9.Washington DC is beautiful but crowded. 10.New York is the best place for a holiday. （三）听短文及短文后的问题，选择正确的答案。（短文及问题读两遍） 11.A.London Park. B.Weston Park. C.Hoar Park. 12.A.Five miles. B.Two miles. C.Three miles. 13.A.In 1671. B.In 1871. C.In 1971. 14.A.10, 000. B.About 1, 000. C.100. 15.A.The best one. B.The better one. C.The good one. 二、单项填空（15分） 16.There are some cartoon ________,such as the Monkey King, Nemo and Shrek. A.character B.favourite C.writers D.favourites 17.It’s against the law for him to rush into ________ house without permission. A.my own private B.him own private C.his own D.own his private 18.Can you help her? She’s ________ deep trouble. A.in B.on C.at D.with 19.There are some trees on ________ sides of the river. A.either B.all C.every D.both 20.About 200 ________ have been sold. https://www.doczj.com/doc/db11675895.html,lion copy https://www.doczj.com/doc/db11675895.html,lions copies https://www.doczj.com/doc/db11675895.html,lions copy https://www.doczj.com/doc/db11675895.html,lion copies 21.She couldn’t help _______ when she heard the bad news. A.cry B.crying
写给未来的你余光中，写给时光散文 从云南回来，哥们告诉我他在烟台期间每天晚上都会失眠，直到凌晨两三点才会入睡，早上六七点就醒来… 我在想，是有什么事吗，让他压力这么大？直到昨天晚上他告诉我：通过我跟你聊天，我知道自己为什么天天失眠了，都到了奔三的年龄了自己的终身大事还没有着落，我急了… 时间已过午夜，窗外的夜在寂静中升起一丝躁动，阵阵风吹来，雨点打在窗棱。我轻轻转动旋钮，关闭床头的台灯，瞬间黑如死寂。在死一般的黑夜里我自己却是如此的失落… 是啊，现在的我，一个尴尬的年龄，不是太大但也不小。一个人在一个陌生的城市游走，周遭的光景亦真亦幻，偌大的城市却寻觅不到属于自己的那一方小小的空间。奋斗的路上累了，跟谁去诉说，好像只有那一张小小的床，那张小床会不会有一天也会不在？如果有这一天，无言就是最后的选择。 隔三差五我就会拨打那个熟悉的号码，和爹娘唠唠家常，说说最近发生的事。身在他乡从来都是报喜不报忧，听着电话那头苍老的声音，这可能就是对他们最大的安慰。我在想，爹娘是悲哀的，不是他们自己悲哀，而是因为我而悲哀，与其这么说倒不如说是自己的悲哀。小的时候，他们为了让我快点长大而任劳任怨；读书的时候，他们为我读书而没日没夜：如今工作了，他们依然在操劳，爹娘总说，你还
没结婚，还要买房子、车子…从我出生到现在，他们心里有的就只是孩子。 对于我来说，我感觉今天我依然是一个失败者，所以我选择了踏实。面对现在的状况，一步步去改善！ 在这个膨胀而偏于物质的世界里，我们彼此都需要另外一个奋斗的目标，对于我这一无所有的北漂人，不知道会不会有一个愿意与我同甘共苦的女孩子，如果有，也不知道什么时候会出现。如果，时光倒流到那最初的街道，你的誓言是否一如瑟瑟的秋风散落天涯，而光阴的流逝却是那不变的曾经！流浪了太多的岁月，一直在时光里等你的到来，我想邀你赴一场和春天的约会。女孩子嘛，除了是女的，心善就好，这就是唯一的要求。不是我着急，有时候想想，人生啊，就像在完成一件件的任务。 处在人生的十字路口，却不是一个人的选择。我在迷茫与坚定里等待，等待那个能够一起赶赴春天约会的人。在这个等待的过程中我依然是那一棵树，宁静，向阳，亦安然，不管春秋冬夏用那敏感的神经抚摸着流云和微风，每天默默得成长！ 哥们儿，愿你心想事成。 [写给未来的你余光中，写给时光散文]相关文章：
《中学教材全解》2012-2013学年七年级地理下（湖南教育版）期中检测题.doc 七年级地理（下）期中检测题 本检测题满分100分，时间60分钟 一、选择题（每小题2分，共60分） 1.亚洲是我们共同的“家”，关于这个“家”的“左邻右舍”，说法正确的是( ) A.东邻欧洲，西濒太平洋 B.南望大洋洲，北濒北冰洋 C.东邻北美洲，西濒大西洋 D.西南隔海与北美洲相望，东北隔海与非洲相望 2.亚洲地势的特点是( ) A.以高原为主 B.地面起伏很大，中部地势高，四周地势较为低平 C.以平原为主 D.西部是山地，中部是平原，东部是高原 3.下列地理事物既是亚洲之最也是世界之最的是( ) A.最长的河流——长江 B.面积最大的国家——中国 C.最大的平原——西西伯利亚平原 D.最深的湖泊——贝加尔湖
4.亚洲是世界上( ) A.平均海拔最低的大洲 B.跨经度最广的大洲 C.面积最大的大洲 D.面积最小的大洲 5.下列对亚洲气候特点的叙述，不正确的是( ) A.气候类型复杂多样 B.季风气候显著 C.温带大陆性气候分布面积最广 D.受海洋影响明显 6.下列各地区的区域文化与当地自然条件组合正确的是( ) A.东南亚人多居住长屋——多地震 B.贝都因人居住帐篷——气候湿润、水草丰美 C.孟加拉人以船为交通工具——气候湿热、河网密布 D.也门的住房大多是平顶——气候湿热 7.造成亚洲大陆气候复杂、南北温差大、东西降水差异大的主要原因是( ) ①纬度因素②海陆因素③洋流因素④地形因素 A.②③ B.①④ C.③④ D.①② 8.南美洲的地形特征是（） A.中间高，四周低 B.高原大陆 C.南北三大纵列带 D.西部是山地，东部高原、平原相间分布[来源:学科网]
余光中一生从事诗歌、散文,驰骋文坛逾半个世纪，颇负盛名。 余光中一篇《写给孩子未来的诗》，朴实的语言夹杂着真挚的育儿道理，使其广为流传。 做一个理想主义者 Be an Idealist 孩子，我希望你自始至终都是一个理想主义者。你可以是农民，可以是工程师，可以是演员，可以是流浪汉，但你必须是一个理想主义者。童年，我们讲英雄故事给你听，并不是一定要你成为英雄，而是希望你具有纯正的品格。
少年，我们让你接触诗歌、绘画、音乐，是为了让你的心灵填满高尚的情趣，这些高尚的情趣会支撑你的一生，使你在最严酷的冬天也不会忘记玫瑰的芳香，理想会使人出众。 孩子，不要为自己的外形担忧，最美貌的女人也会因为庸俗而令人生厌，通向理想的途径往往不尽如人意，而你亦会为此受尽磨难，但是，孩子你尽管去争取，理想主义者的结局悲壮而绝不可怜。 做一个诚实、踏实的人 Be an honest man 其次，孩子我希望你是个踏实的人。人生太过短促，而虚的东西又太多，你很容易眼花缭乱，最终一事无成。 如果你是个美貌的女孩，年轻的时候会有许多男性宠你，你得到的东西太过容易，这会使你流于浅薄和虚浮；如果你是个极聪明的男孩，又会以为自己能够成就许多大事而流于轻佻。
记住，每个人的能力有限，我们活在世上能做好一件事足矣。 写好一本书，做好一个主妇。不要轻视平凡的人，不要投机取巧，不要攻击自己做不到的事。你长大后会知道，做好一件事太难，但绝不要放弃。 你要懂得珍惜感情。不管男人女人，不管墙内墙外，相交一场实在不易。
希望你不要媚俗 Be a Man of Integrity 希望你不要媚俗。你是个独立的人，无人能抹杀你的独立性，除非你向世俗妥协。要学会欣赏真，要在重重面具下看到真。 世上圆滑标准的人很多，但出类拔萃的人极少。而往往出类拔萃又隐藏在卑琐狂荡之下。在形式上我们无法与既定的世俗争斗，而在内心我们都是自己的国王。
期末检测题 （本检测题满分：120分，时间：120分钟） 一、选择题（每小题3分，共36分） 1.的相反数和绝对值分别是（ ） A. B. C. D. 2.如果和互为相反数，且 ，那么的倒数是（ ） A.b 21- B.b 21 C.b 2- D. 3.(2020·湖南长沙中考)下列各图中，∠1与∠2互为余角的是( ) A B C D 4.(2020·北京中考改编)有理数a ，b 在数轴上的对应点的位置如图所示，则正确的结论 是( ) A.a >-2 B.a <-3 C.a >-b D.a <-b 5.已知有一整式与的和为，则此整式为（ ） A. B. C. D. 6.(2020·吉林中考)小红要购买珠子串成一条手链.黑色珠子每个a 元,白色珠子每个b 元,要串成如图所示的手链,小红购买珠子应该花费( ) A.(3a +4b )元 B.(4a +3b )元 a +b )元 D.3(a +b )元 第6题图 7.（2020·河北中考）图中的三视图所对应的几何体是（ ） C. D. 第7题图
8.（2020·吉林中考）如图，有一个正方体纸巾盒，它的平面展开图是( ) 第8题图 9.2条直线最多有1个交点，3条直线最多有3个交点，4条直线最多有6个交点，…,那么6条直线最多有（ ） A.21个交点 B.18个交点 C.15个交点 D.10个交点 10.如图，直线 和 相交于点， 是直角， 平分 ， ，则 的大小为（ ） A. B. C. D. 第11题图 11.（2020?山东泰安中考）如图，AB ∥CD ，∠1=58°，FG 平分∠EFD ，则∠FGB 的度数等于（ ） A.122° B.151° C.116° D.97° 12. (2020·山西中考)如图，直线a ∥b ，一块含60°角的直角三角板ABC (∠A ＝60°)按如图所示放置.若∠1＝55°，则∠2的度数为( ) A.105° B.110° C.115° D.120° 二、填空题（每小题3分，共24分） 13.如果 的值与 的值互为相反数，那么等于_____. 14.足球比赛的记分规则是：胜一场得3分，平一场得1分，负一场得0分．一队打14场，负5场，共得19分，那么这个队共胜了_____场. 第11题图 第12题图
June 10, 2016 Dear 28-year-old Joezie: Perhaps you have already abandoned this English name but just allow me to use it in this aged letter for the last time. Are you still a handsome and romantic man like who you are 10 years ago? I don’t mind if you are more handsome than me. No matter what kind of job you are occupied in, family must always be principal. Do you still remember how to spell “LOVE”? It is “T-I-M-E”. A phone call, a video chat, and go home. I know it is quite time-consuming to make it home, but just don’t make it a frequently-used excuse. Go home, and be the kid of your parents. You must have got married now and let me guess your wife’s name. Okay, I can’t guess it without knowing that who you meet during this long period and feeling what exact chemical is in both you and the other side. As a completely inexperienced single dog, I can’t teach you any skills when it comes to how to preserve y our love. But as Fan Weiqisings , “there’s no shortcut to happiness but experiencing it whole-heartedly is the only way”. Loyalty and sincerity, I think, are the keys to long-lasting love.I hope that you can live up to it. Oh, a lovely cute baby must have already been given birth to! Quite annoying it is to look after a live alarm that might go off or get pissed off at any time. But it is the little cute baby that make your house a place called HOME. And you can’t have forgotten to teach the baby Wuyanghua! Maybe you can’t live in Powei for the sake of a better living condition, but the language is the symbol of your identity and the root of your journey. Please don’t make you and your kid rootless catkins. I hope that you are doing the job where you find interest and passion. I guess it is related to Big Data, anabused phrase in 2016. I know this must be promising and I hope that you can make it meaningful to your motherland. Please always keep your initial intention in mind and basing on this, make a difference. I’m glad that you can spend your time reading this letter from a naive 18-year-old boy. No matter what you choose, I’m backing you up! You don’t need to reply this letter. Just write another one to your future self! Sincerelyyours, 18-year-old Joezie
期末检测题 （时间：120分钟，满分：120分） 一、选择题（每小题3分，共36分） 1.下列运算中，错误的有（ ） ①12 5 1144251 =； ②4)4(2±=-； ③2222 2-=-=-； ④ 20 9 5141251161=+=+. A.1个 B.2个 C.3个 D.4个 2.如图是用4个相同的小矩形与1个小正方形密铺而成的正方形图案，已知该图案的面积为 ，小正方形的面积为，若用表示小矩形的两边长，请观察图案，指出以 下关系式中不正确的是（ ） A. B. C. D. 3.已知，且 ，则（ ） A. B. C. D. 4.若不等式)(3 1 2x m m -> -的解集为，则的值为（ ） A.32 B.12 C.2 D.4 5.不论 为什么实数，代数式 的值（ ） A.总不小于2 B.总不小于7 C.可为任何实数 D.可能为负数 6.两码头相距千米，一船顺水航行需小时，逆水航行需小时，那么水流速度为（ ） A. b s a s 22- B.a s b s 22- C.b a ab -2 D.a b ab -2 7.设一项工程的工程量为1，甲单独做需要天完成，乙单独做需要天完成，则甲、乙两人合做一天的工作量为（ ） A. B. 1a b + C.2a b + D.11 a b +
8.某工地调来人挖土和运土,已知人挖出的土人恰好能全部运走,怎样调配劳动力使挖 出的土能及时运走且不窝工，解决此问题可设派人挖土,其他人运土，列方程: ① ,② 3x ,③7213x x -=, ④372x x =-. 上述所列方程正确的有( ) A.1个 B.2个 C.3个 D.4个 9.如果与 互补，与 互余，则 与 的关系是（ ） A. B. C. D.以上都不对 10.如图，已知直线和 相交于点， 是直角， 平分，， 则的大小为（ ） A. B. C. D. 11.如图，直线相交于点， ∥ ．若 ，则∠ 等于（ ） A.70° B.80° C.90° D.110° 12.如图， ∥ ， 和相交于点，，，则∠等于（ ） A.40° B.65° C.75° D.115°
《写给未来的你》 孩子，我希望你自始至终都是一个理想主义者。 你可以是农民，可以是工程师，可以是演员，可以是流浪汉，但你必须是个理想主义者。 童年，我们讲英雄故事给你听，并不是一定要你成为英雄，而是希望你具有纯正的品格。 少年，我们让你接触诗歌、绘画、音乐，是为了让你的心灵填满高尚的情趣。 这些高尚的情趣会支撑你的一生，使你在最严酷的冬天也不会忘记玫瑰的芳香。 理想会使人出众。 孩子，不要为自己的外形担忧。 理想纯洁你的气质，而最美貌的女人也会因为庸俗而令人生厌。 通向理想的途径往往不尽如人意，而你亦会为此受尽磨难。 但是，孩子，你尽管去争取，理想主义者的结局悲壮而绝不可怜。 在貌似坎坷的人生里，你会结识许多智者和君子，你会见到许多旁人无法遇到的风景和奇迹。 选择平庸虽然稳妥，但绝无色彩。 不要为蝇头小利放弃自己的理想，不要为某种潮流而改换自己的信念。 物质世界的外表太过复杂，你要懂得如何去拒绝虚荣的诱惑。 理想不是实惠的东西，它往往不能带给你尘世的享受。 因此你必须习惯无人欣赏，学会精神享受，学会与他人不同。
其次，孩子，我希望你是个踏实的人。 人生太过短促，而虚的东西又太多，你很容易眼花缭乱，最终一事无成。 如果你是个美貌的女孩，年轻的时候会有许多男性宠你，你得到的东西太过容易，这会使你流于浅薄和虚浮； 如果你是个极聪明的男孩，又会以为自己能够成就许多大事而流于轻佻。 记住，每个人的能力有限，我们活在世上能做好一件事足矣。 写好一本书，做好一个主妇。 不要轻视平凡的人，不要投机取巧，不要攻击自己做不到的事。 你长大后会知道，做好一件事太难，但绝不要放弃。? 得和珍惜感情。 不管男人女人，不管墙内墙外，相交一场实在不易。 交友的过程会有误会和摩擦，但想一想，诺大世界，有缘结伴而行的能有几人？ 你要明白朋友终会离去，生活中能有人伴在身边，听你倾谈，倾谈给你听，就应该感激。 要爱自己和爱他人，要懂自己和懂他人。 你的心要如溪水般柔软，你的眼波要像春天般明媚。 你要会流泪，会孤身一人坐在黑暗中听伤感的音乐。 你要懂得欣赏悲剧，悲剧能丰富你的心灵。? 希望你不要媚俗。 你是个独立的人，无人能抹杀你的独立性，除非你向世俗妥协。? 要学会欣赏真，要在重重面具下看到真。
初中物理学习材料 鼎尚图文制作整理 奇异的容器 能不能制造出这样一种容器，使流出的水不顾容器里面液体的液面在逐渐降低，始终流出得很均匀而不会越来越慢呢？也许你会认为这是办不到的。 但是这是完全可以办到的。如下图所画的瓶正是这样一种奇异的容器。这个容器是一个普通的窄颈瓶，通过它的塞子，插着一根玻璃管。如果你把比玻璃管下端更低的龙头打 开，液体就会均匀地往外流，一直到容器里的液面降低到跟玻璃管下端相平为止。如果把玻璃管插到差不多与水龙头平齐的地方，你就可以使全部液体均匀地从容器里流出，虽然这是 一股很弱的水流。 这是什么缘故呢？让我们想一想，在龙头开着的时候（如图所示），容器里会发生些 什么情况？水向外流的时候，容器里的液面就会下降，外面的空气就通过玻璃管从水下面流进瓶里的稀薄空气里。气泡一个一个从水里冒上来，聚集在容器上部的水面上。这时候在那么高的水平面上所受的压力等于大气的压力。也就是说，从龙头流出的水，只是在 那一层水的压力下往外流，因为容器内外的大气压力是可以相互抵消的。也因为那一层水的高度是不变的，所以从龙头流出的水始终保持着同样的速度，是一点也不奇怪的。 现在请你回答一个问题：如果拔去跟玻璃管下端相平的塞子，那么水会流出得多快 呢？
原来水完全不往外流（当然这只是在孔非常小，可以不予计算的时候才是这样。不然的话，水会在同孔的宽度一样厚的那一薄层水的压力下向外流）。事实上，这里的内外压力都跟大气压力相等，没有什么力能够迫使水向外流。 可是如果你把那个比玻璃管下端高的塞子拔出来，那就不但没有水从容器里流出，外面的空气还会从这里流进容器里。为什么？原因很简单：在容器这一部分里，空气的压力比外面的大气压力要小。 有这种特别性质的容器是物理学家马里奥特发明出来的，所以这样的容器就叫做“马里奥特容器”。 静脉滴注中的压强知识 1．当输液针刚插入瓶内时，有时为何会有药液冲出？ 当护士用针筒把药剂压入瓶子内时，里面空气体积变小，瓶内空气压强增大，因 ，所以当输液针头插入瓶口时，就有药液被压出来，速度很快，直至。这样一来造成了不少药液的损失，有经验的护士总是在压入药剂后抽出一部分空气，使。 2．输液瓶口为何要插两根管？ 假设刚开始时瓶内空气压强等于大气压，瓶口处的压强为，（如图所示）由于一标准大气压能支持高水柱，所以。当输液针插入瓶口后，因，所以有一部分药液经输液管流出。在药液高度降低时，瓶内空气体积变大压强变小，减小，当时，药
写给未来的你男一 （领）在浩渺的时空里 我们每个人都站在 过去和未来之间 既秉承着过去对我们的期许 也怀揣着我们 对未来的期盼 女一 （领）这一代一代 传承的期许和期盼 缔结为接力千载的信笺 男二 （领）写给未来的你 写给所有的今天和明天 女二 （领）写给未来的你 周游列国的百家曾用竹简 把四海升平的梦写给今天
(齐)大学之道在明明德 在亲民在止于至善 计利当计天下利 求名当求万世名 空谈误国实干兴邦 女一 (领)写给未来的你 出使西域的张骞 七下西洋的郑和 曾用丝路驼铃海路风帆 把连接四海情结万邦的梦写给今天 男一 （领）有朋自远方来不亦乐乎 四海之内皆兄弟也 (齐)礼之用和为贵 见利思义见危授命 美人之美美美与共 天下大同
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第十三、十四章中考典题补充 1. 2.（2015?天津中考）图1为四冲程汽油机工作过程中的某冲程示意 图，该冲程为（） 蚁图1 A.吸气冲程 B.压缩冲程 C.做功冲程 D.排气冲程 解析：由图知，两个气门都关闭，火花塞产生电火花，活塞向下运动，因此是做功冲程，故Ｃ选项正确。 答案：C 2. (2015?山东泰安中考)四冲程内燃机工作时，哪个冲程将机械能转化为内能( ) A.压缩冲程 B.做功冲程 C.吸气冲程 D.排气冲程 解析：内燃机是将内能转化为机械能的机器，它的一个工作循环包括：吸气、压缩、做功、排气四个冲程，其中压缩冲程是将机械能转化为内能；做功冲程是将内能转化为机械能，故A选项正确。 答案：A 3. (2015?湖北宜昌中考)为节约能源，需要提高热机的效率，下列措施中不能提高热机效 率的是( ) A.尽量使燃料充分燃烧 B.尽量减少热机部件间的摩擦 C.尽量减少废气带走的热量 D.尽量增加热机的工作时间 解析：提高热机效率具有重要的经济效益和社会效益，在物理学中，提高热机效率就是增加有用功或减少额外功。在热机中，使燃料充分燃烧可以提高热机效率；减少废气带走的热量可以提高热机效率；减少热机部件间的摩擦也可以提高热机效率；增加热机的工作时间不能提高热机效率。
答案：D 4. (2013?四川自贡中考)如图2所示流程是用来说明单缸四冲程汽油机的一个工作循环及 涉及的主要能量转化情况。对图中①②③④的补充正确的是( ) 图2 A.①做功冲程②内能转化为机械能③压缩冲程④机械能转化为内能 B.①压缩冲程②内能转化为机械能③做功冲程④机械能转化为内能 C.①压缩冲程②机械能转化为内能③做功冲程④内能转化为机械能 D.①做功冲程②机械能转化为内能③压缩冲程④内能转化为机械能 解析：压缩冲程中，活塞压缩汽缸内的气体，使气体内能增大，将机械能转化为内能； 做功冲程中，燃料燃烧产生高温高压的燃气推动活塞运动，将内能转化为机械能。所以C选项正确。 答案：C 5. (2013?山东济宁中考)我国研制的“神舟九号”试验飞船在返回地面通过大气层的飞行 中，下列说法中不正确的是( ) A.飞船的机械能保持不变 B.飞船的一部分机械能转化为内能 C.飞船的重力势能越来越小 D.飞船的外表温度会升高 解析：飞船在返回地面通过大气层的飞行中，飞船要克服空气的摩擦做功，飞船的一部分机械能转化为内能，飞船的机械能减少，而内能增加，外表温度升高，能量的总量不变，B、D选项正确，A选项不正确；飞船的高度越来越小，因此飞船的重力势能越来越小，C选项正确。 答案：A 6. （2014·甘肃白银中考）如图3所示是四冲程汽油机的两个冲程，甲图显示的是汽油机的冲程，乙图中是能转化为能。 甲乙