[1] Defendant first contends that it was error for the court to permit David B. Maddrey to testify that, in his opinion as an expert, the fire was not caused by electrical malfunction. We disagree. Generally, “[a]n expert witness is a person who is better qualified than the jury to form an opinion from facts in evidence.” State v. Brackett, 55 N.C. App. 410, 416, 285 S.E. 2d 852, 857, rev’d on other grounds, 306 N.C. 138, 291 S.E. 2d 660 (1982). Stated alternatively, “[t]he essential question determining the admissibility of opinion evidence is whether the witness, through study and experience, has acquired such skill that he is better qualified than the jury to form an opinion as to the subject matter to which his testimony applies.” State v. Phifer, 290 N.C. 203, 213, 225 S.E. 2d 786, 793 (1976). In the present case there was sufficient evidence to qualify the witness as an expert in the “field of electrical causation of fires.” Mr. Maddrey has been employed since 1960 as an electrical inspector for the North Carolina Department of Insurance. He holds an “unlimited electrical contractor’s license,” has attended seminars on the effects of electrically caused fires and has aided the S.B.I. in determining the cause or causes of approximately 25 other fires. It is irrelevant that Maddrey has received no formal degree in view of his extensive experience and practical training. He was clearly more qualified than the jury to form an opinion from the facts presented about the school’s electrical system and was therefore properly accepted as an expert witness.
[2] Defendant next maintains that it was error for the court to admit testimony regarding S.B.I. agent David Campbell’s impressions of defendant’s emotional state as he was interviewed after the fire. Agent Campbell’s testimony contained the following:
Q. What, if anything, did you observe about James Khork’s reaction to that fire?
Mr. Gaines: Object.
COURT: Overruled.
A. He would not look me in the eyes.
Mr. Gaines: Move to strike that testimony.
*154COURT: Overruled.
A. His heart, I could see his heart (inaudible) in his throat.
Defendant maintains that this testimony is subjective, conclusive and blatantly prejudicial. We cannot agree. “The emotion displayed by a person on a given occasion is a proper subject for opinion testimony by a non-expert witness.” State v. Looney, 294 N.C. 1, 14, 240 S.E. 2d 612, 619 (1978) (witness properly allowed to testify that “the man’s eyes ‘lit up’ ” upon meeting another); 1 Stansbury, North Carolina Evidence § 129 (Brandis rev. 1973). Campbell’s statements merely constituted a “shorthand description” of defendant’s nervous reaction to being questioned and in no way precluded the trier of fact from making an independent evaluation of the evidence presented. State v. Myers, 299 N.C. 671, 674, 263 S.E. 2d 768, 771 (1980).
[3] Defendant next assigns as error the trial court’s denial of his motion to dismiss on the grounds that the circumstantial evidence presented by the State was insufficient to sustain a guilty verdict. In support of his contention, defendant cites the proposition that an extrajudicial uncorroborated confession of a defendant, standing alone, is insufficient to submit the question of defendant’s guilt to the jury. State v. Thompson, 287 N.C. 303, 214 S.E. 2d 742 (1975), modified mem., 428 U.S. 908, 96 S.Ct. 3215, 49 L.Ed. 2d 1213 (1976). Although valid, defendant’s authority is misapplied. In the present case, the State has offered sufficient evidence of extrinsic circumstances which suggest that defendant’s “confessions” were no mere offhand jest and which, when viewed with his admissions, clearly point to defendant as the perpetrator of the crime. These extrajudicial confessions contained details that were unknown to all but the arsonist until the official police investigation was completed. Defendant revealed that he knew both the exact location of the fire’s place of origin, beside his teacher’s desk, and the “incendiary” means by which the fire was ignited. Evidence of the expression of these details clearly constitutes sufficient corroborative evidence which gives rise to a reasonable inference of defendant’s guilt. In this jurisdiction, “[i]f the evidence adduced at trial gives rise to a reasonable inference of guilt, it is for the [trier of fact] to decide whether the facts shown satisfy [him] beyond a reasonable doubt of defend*155ant’s guilt.” State v. Jones, 303 N.C. 500, 504, 279 S.E. 2d 835, 838 (1981). We must also remind defendant that the State’s evidence need not exclude every reasonable hypothesis of innocence. Id. The verdict is not defective simply because it fails to disprove the culpability of all those with access to the building. Although circumstantial, the evidence was clearly sufficient to withstand a motion to dismiss and to provide a logical and reasonable inference of defendant’s guilt.
[4] We are persuaded, however, by the contention that defendant’s commitment to the Division of Youth Services is not justified by the record of the dispositional hearing. G.S. 7A-649 provides that in the case of any juvenile found to be delinquent, a judge may impose any of ten dispositional alternatives. Yet Article 52 also directs that the judge shall select the “least restrictive disposition . . . that is appropriate to the seriousness of the offense, the degree of culpability indicated . . . and the age and prior record of the juvenile. A juvenile should not be committed . . . if he can be helped through community-level resources.” G.S. 7A-646. Commitment is appropriate only if the judge finds “that (1) alternatives to commitment available in G.S. 7A-649 have been unsuccessfully attempted or are inappropriate, and (2) the juvenile’s behavior is a threat.” In re Vinson, 298 N.C. 640, 672, 260 S.E. 2d 591, 610 (1979) (citing G.S. 7A-652) [emphasis original]. This statutory framework was designed to provide flexible treatment in the “best interests” of both the juvenile and the State and to accordingly restrict the option of institutionalization to those “extraordinary situation^]” where “no reasonable alternative [is] open to the court. . . .” In re Brownlee, 301 N.C. 532, 551-52, 272 S.E. 2d 861, 873 (1981).
The statutory standard has therefore been held to direct that the trial judge recite detailed findings in support of either test enunciated under G.S. 7A-652, and require “that those enumerated findings are supported by some evidence in the record of the dispositional hearing.” Vinson, 298 N.C. at 672, 260 S.E. 2d at 610 [emphasis original]. In the present case, as in Vinson, there was no evidence of the inappropriateness of probation presented at the dispositional hearing. Indeed, no evidence to support an order of commitment was presented. We believe that the trial court clearly erred. Where no evidence of the appropriateness of incarceration is presented in the dispositional hearing, defendant *156may not be committed based upon the perceived seriousness of the offense alone. Such actions would otherwise render the dispo-sitional hearing a useless formality and ignore the legislative directive that the commitment of delinquent juveniles is presumptively inappropriate. We, therefore, sustain defendant’s final assignment of error and direct the trial court to apply an appropriate alternative based upon the evidence presented on remand.
Affirmed in part, vacated in part. Remanded for new disposi-tional hearing.
Judges WHICHARD and JOHNSON concur.